Arrays and Array Lists Ch.7 Test Bank Docx - Big Java Early Objects 5e Complete Test Bank by Cay S. Horstmann. DOCX document preview.
Package Title: Test Bank
Course Title: Big Java
Chapter Number: 7 Arrays and Array Lists
Question type: Multiple Choice
1) Consider the following line of code:
int[] somearray = new int[30];
Which one of the following options is a valid line of code for displaying the twenty-eighth element of somearray?
a) System.out.println(somearray[28]);
b) System.out.println(somearray(28));
c) System.out.println(somearray(27));
d) System.out.println(somearray[27]);
Title: Which code displays the 28th element of somearray?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
2) Identify the correct statement for defining an integer array named numarray of ten elements.
a) int[] numarray = new int[9];
b) int[] numarray = new int[10];
c) int[10] numarray;
d) int numarray[10];
Title: Which statement defines integer array numarray with ten elements?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
3) Which one of the following statements is a valid initialization of an array named somearray of ten elements?
a) int[] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
b) int somearray[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
c) int[10] somearray = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
d) int somearray[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
Title: Which array initialization statement is invalid?
Difficulty: Medium
Section Reference 1: 7.1 Arrays
4) What is the output of the following code snippet?
int[] myarray = { 10, 20, 30, 40, 50 };
System.out.print(myarray[2]);
System.out.print(myarray[3]);
a) 1050
b) 2030
c) 3040
d) 4050
Title: What are values of the elements at the given array indexes?
Difficulty: Medium
Section Reference 1: 7.1 Arrays
5) What is the result of executing this code snippet?
int[] marks = { 90, 45, 67 };
for (int i = 0; i <= 3; i++)
{
System.out.println(marks[i]);
}
a) The code snippet does not give any output.
b) The code snippet displays all the marks stored in the array without any redundancy.
c) The code snippet causes a bounds error.
d) The code snippet executes an infinite loop.
Title: What is output of for loop that traverses given array?
Difficulty: Medium
Section Reference 1: 7.1 Arrays
6) What is the valid range of index values for an array of size 10?
a) 0 to 10
b) 1 to 9
c) 1 to 10
d) 0 to 9
Title: What is the range of index values for an array of size 10?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
7) Which one of the following statements is correct about the given code snippet?
int[] somearray = new int[6];
for (int i = 1; i < 6; i++)
{
somearray[i] = i + 1;
}
a) The for loop initializes all the elements of the array.
b) The for loop initializes all the elements except the first element.
c) The for loop initializes all the elements except the last element.
d) The for loop initializes all the elements except the first and last elements.
Title: Which statement is true about this for loop that initializes an array?
Difficulty: Hard
Section Reference 1: 7.1 Arrays
8) What is the output of the given code snippet?
int[] mynum = new int[5];
for (int i = 1; i < 5; i++)
{
mynum[i] = i + 1;
System.out.print(mynum[i]);
}
a) 2345
b) 1234
c) 1345
d) 1111
Title: What is output of this for loop that traverses/displays array elements?
Difficulty: Medium
Section Reference 1: 7.1 Arrays
9) Which one of the following statements is correct for the given code snippet?
int[] number = new int[3]; // Line 1
number[3] = 5; // Line 2
a) Line 2 declares and initializes an array of three elements with value 5.
b) Line 2 causes a bounds error because 3 is an invalid index number.
c) Line 2 initializes the third element of the array with value 5.
d) Line 2 initializes all the elements of the array with value 5.
Title: Which statement is true for snippet with array bounds error?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
10) What is displayed after executing the given code snippet?
int[] mymarks = new int[10];
int total = 0;
Scanner in = new Scanner(System.in);
for (int cnt = 1; cnt <= 10; cnt++)
{
System.out.print("Enter the marks: ");
mymarks[cnt] = in.nextInt();
total = total + mymarks[cnt];
}
System.out.println(total);
a) The code snippet displays the total marks of all ten subjects.
b) The for loop causes a run-time time error on the first iteration.
c) The code snippet causes a bounds error.
d) The code snippet displays zero.
Title: Which is result of for loop that fills an array and totals its elements?
Difficulty: Hard
Section Reference 1: 7.1 Arrays
11) When an array myArray is only partially filled, how can the programmer keep track of the current number of elements?
a) access myArray.length()
b) maintain a companion variable that stores the current number of elements
c) access myArray.currentElements()
d) access myArray.length() - 1
Title: How is a partially filled array maintained?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
12) Suppose you wish to write a method that returns the sum of the elements in the partially filled array myArray. Which is a reasonable method header?
a) public static int sum(int[] values)
b) public static int sum()
c) public static int sum(int[] values, int currSize)
d) public static int sum(int[] values, int size, int currSize)
Title: What is a reasonable method header for computing the sum of elements in a partially filled array?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithims
13) Which code snippet prints out the elements in a partially filled array of integers?
a)
for (int i = 0; i < myArray.length(); i++)
{
System.out.print(myArray[i]);
}
b)
for (int i = 0; i < myArray.currLength(); i++)
{
System.out.print(myArray[i]);
}
c)
for (int i = 0; i < currLength; i++)
{
System.out.print(myArray[i]);
}
d)
for (int i = 0; i < myArray.length(); i++)
{
System.out.print(myArray[currLength]);
}
Title: Which code snippet prints out a partially filled array?
Difficulty: Medium
Section Reference 1: 7.1 Arrays
14) In a partially filled array, the number of slots in the array that are not currently used is
a) the length of the array minus the number of elements currently in the array
b) the number of elements currently in the array minus the length of the array
c) the length of the array plus the number of elements currently in the array
d) the number of elements currently in the array
Title: How do you calculate remaining space in a partially filled array?
Difficulty: Easy
Section Reference 1: 7.1.3 Partially-Filled Arrays
15) Complete the following code snippet with the correct enhanced for loop so it iterates over the array without using an index variable.
String[] arr = { "abc", "def", "ghi", "jkl" };
___________________
{
System.out.print(str);
}
a) for (String str : arr)
b) for (str : String arr)
c) for (str[] : arr)
d) for (arr[] : str)
Title: What is the correct enhanced for loop to iterate over the array
Difficulty: Medium
7.2Section Reference 1: 7.2 The Enhanced for Loop
16) Which statements are true about the buffer overrun attack launched over the Internet in 1988?
I. The buffer overrun exploited a program that was written in C running on the Unix operating system
II. The Java programming language generates a run-time exception when buffer overrun occurs
III. In recent years computer attacks have lessened
a) I, II
b) I, III
c) II, III
d) I, II, III
Title: Which statements are true about the buffer overrun attack?
Difficulty: Easy
Section Reference 1: 7.1 Arrays
Section Reference 2: Random Fact 7.1
17) What is the result of the following code?
for (double element : values)
{
element = 0;
}
a) The elements of the array values are initialized to zero.
b) The elements of the array element are initialized to zero.
c) The first element of the array values is initialized to zero.
d) The array values is not modified.
Title: What is the result of the enhanced for loop?
Difficulty: Medium
7.2Section Reference 1: 7.2 The Enhanced for Loop
18) Which statements about the enhanced for loop are true for arrays of primitve data?
I. It is suitable for all array algorithms
II. It does not allow the contents of the array to be modified
III. It does not require the use of an index variable
a) I, II
b) I, III
c) II, III
d) I, II, III
Title: Which statements about the enhanced for loop are true?
Difficulty: Easy
7.2Section Reference 1: 7.2 The Enhanced for Loop
19) The enhanced for loop
a) is convenient for traversing all elements in an array
b) is convenient for traversing elements in a partially filled array
c) is only used for arrays of integers
d) is used to initialize all array elements to a common value
Title: What is true about the enhanced for loop?
Difficulty: Easy
Learning Objective 1: LO 7.2 Know when to use the enhanced for loop.
Section Reference 1: 7.2 The Enhanced for Loop
20) When the order of the elements is unimportant, what is the most efficient way to remove an element from an array?
a) Delete the element and move each element after that one to a lower index.
b) Replace the element to be deleted with the last element in the array.
c) Replace the element to be deleted with the first element in the array.
d) Replace the element with the next element.
Title: What is the most efficient way to remove an element in an unordered array?
Difficulty: Easy
Section Reference 1: 7.3 Common Array Algorithms
7.3
21) When an array reading and storing input runs out of space
a) the program could be recompiled with a bigger size for the array.
b) the array could be "grown" using the growArray method.
c) it automatically resizes to accommodate new elements.
d) the array could be "grown" using the new command and the copyOf method.
Title: What happens when an array runs out of space?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
22) It may be necessary to "grow" an array when reading inputs because
a) the number of inputs may not be known in advance.
b) arrays in Java must be resized after every 100 elements.
c) arrays are based on powers of two.
d) the only alternative is a bounds exception.
Title: Why might it be necessary to grow an array when reading inputs?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
23) The binary search is faster than the linear search, providing
a) the size of the array is a power of two.
b) the elements of the array are ordered.
c) the elements of the array are unordered.
d) the element being searched for is actually in the array.
Title: What is true about the binary search?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
Section Reference 2: Special Topic 7.2
24) Which statements about array algorithms are true?
I. The array algorithms are building blocks for many programs that process arrays
II. Java contains ready-made array algorithms for every problem situation
III. It is inefficient to make multiple passes through an array if you can do everything in one pass
a) I, II
b) I, III
c) II, III
d) I, II, III
Title: Which statements about array algorithms are true?
Difficulty: Easy
Section Reference 1: 7.4 Problem Solving: Adapting Algorithms
25) Suppose you wish to use an array to solve a new problem. What is the first step to take in finding a solution?
a) structure a program using methods
b) adapt a built-in array algorithm
c) decompose the problem into steps
d) assemble a test program and run it
Title: What is the first step in working with arrays to solve a problem?
Difficulty: Easy
Section Reference 1: 7.4 Problem Solving: Adapting Algorithms
26.) Suppose you wish to process an array of values and eliminate any potential duplicate values stored in the array. Which array algorithms might be adapted for this?
a) find the minimum
b) remove an element
c) add an element
d) calculate the sum of the elements
Title: Which array algorithms might be adapted to solve the "remove duplicates" problem?
Difficulty: Medium
Section Reference 1: 7.4 Problem Solving: Adapting Algorithms
27) Which code snippet finds the largest value in an array that is only partially full?
a)
double largest = values[0];
for (int i = 1; i < values.length; i++)
{
if (values[i] > largest)
{
largest = values[i];
}
}
b)
double largest = values[0];
for (int i = 1; i < values.length; i++)
{
if (values[i] < largest)
{
largest = values[i];
}
}
c)
double largest = values[0];
for (int i = 1; i < currSize; i++)
{
if (values[i] > largest)
{
largest = values[i];
}
}
d)
double largest = values[0];
for (int i = 1; i < currSize; i++)
{
if (values[i] < largest)
{
largest = values[i];
}
}
Title: Which snippet finds the maximum in a partially full array?
Difficulty: Easy
Section Reference 1: 7.4 Problem Solving: Adapting Algorithms
28) When a Java program terminates and reports an exception, the error message contains which pieces of useful information?
I. The compile and revision control history of the source code changes that caused the error
II. The name of the exception that occurred
III. The stack trace
a) I, II
b) I, III
c) II, III
d) I, II, III
Title: Which pieces of useful information are contained in an exception report?
Difficulty: Easy
Section Reference 1: 7.4 Problem Solving: Adapting Algorithms
Section Reference 2: Programming Tip 7.2
29) Which code snippet calculates the sum of all the even elements in an array values?
a)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
if ((values[i] % 2) == 0)
{
sum += values[i];
}
}
b)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
if ((values[i] % 2) == 0)
{
sum++;
}
}
c)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
if ((values[i] / 2) == 0)
{
sum += values[i];
}
}
d)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
if ((values[i] / 2) == 0)
{
sum++;
}
}
Title: Which snippet calculates the sum of elements that are even?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
30) Which code snippet calculates the sum of all the elements in even positions in an array?
a)
int sum = 0;
for (int i = 1; i < values.length; i+=2)
{
sum++;
}
b)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
sum++;
}
c)
int sum = 0;
for (int i = 0; i < values.length; i++)
{
sum += values[i];
}
d)
int sum = 0;
for (int i = 0; i < values.length; i = i + 2)
{
sum += values[i];
}
Title: Which snippet calculates the sum of elements that are in even positions?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
31) Consider using a deck of cards as a way to visualize a shuffle algorithm. When two cards shuffle their position, what has to happen to the size of the array holding them?
a) it increases by one
b) it decreases by one
c) it stays the same
d) it increases by two
Title: What happens to the array size when two cards are swapped?
Difficulty: Easy
Section Reference 1: 7.5 Problem Solving: Discovering Algorithms by Manipulating Physical Objects
32) Consider the telephone book as a physical object that can help understand algorithms. What kind of algorithm might be visualized using it?
a) Sorting
b) Searching
c) Finding the maximum
d) Monte Carlo methods
Title: What algorithms can be understood through the phone book as a physical object?
Difficulty: Easy
Section Reference 1: 7.5Problem Solving: Discovering Algorithms by Manipulating Physical Objects
33) Why is the use of physical objects helpful in algorithm design?
a) It simulates the way the computer actually implements the algorithm
b) It is more abstract than using a pencil and paper
c) Because the constraints on physical things are the same as the constraints on bits and bytes
d) Many people feel it is less intimidating than drawing diagrams
Title: Why is the use of physical objects helpful in algorithm design?
Difficulty: Easy
Section Reference 1: 7.5 Problem Solving: Discovering Algorithms by Manipulating Physical Objects
34) Which statement(s) about the size of a Java array, array list, and string are true?
I. The syntax for determining the size of an array, an array list, and a string in Java is consistent among the three
II. The string uses s.size(), while the array list uses a.length()
III. The array uses a.length, which is not a method call
a) I
b) II
c) III
d) II, III
Title: Which statements about the size of a Java array, array list, and a string are true?
Difficulty: Medium
7.7Section Reference 1: 7.7 Array Lists
35) If a programmer confuses the method required for checking the length of a string and uses size() instead of length(), what will happen?
a) The program will crash.
b) The program will not compile.
c) The program will run but will produce an uncertain result.
d) The compiler will automatically correct the error.
Title: What happens if the wrong method is used to get the length of a string?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
36) Babbage’s machine for automatically producing printed tables was called
a) the slide rule.
b) the difference engine.
c) the mechanical calculator.
d) the cog wheel.
Title: What was the Babbage machine called?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
37) Java 7 introduced enhanced syntax for declaring array lists, which is termed
a) angle brackets.
b) method lists.
c) diamond syntax.
d) symmetric slants.
Title: What is the term for the syntax Java 7 introduced for declaring array lists?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
38) The following statement gets an element from position 4 in an array:
x = a[4];
What is the equivalent operation using an array list?
a) x = a.get(4);
b) x = a.get();
c) x = a.get[4];
d) x = a[4];
Title: Which statement gets an element from the array list?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
39) Which statements are true regarding the differences between arrays and array lists?
I. Arrays are better if the size of a collection will not change
II. Array lists are more efficient than arrays
III. Array lists are easier to use than arrays
a) I, II
b) I, III
c) II, III
d) I, II, III
Title: Which statements are true regarding the differences between arrays and array lists?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
40) What is the value of the count variable after the execution of the given code snippet?
ArrayList<Integer> num = new ArrayList<Integer>();
num.add(1);
num.add(2);
num.add(1);
int count = 0;
for (int i = 0; i < num.size(); i++)
{
if (num.get(i) % 2 == 0)
{
count++;
}
}
a) 1
b) 2
c) 0
d) 3
Title: What is value of count variable after this for loop traverses the array list?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
41) Which one of the following code snippets accepts the integer input in an array list named num1 and stores the odd integers of num1 in another array list named oddnum?
a)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> oddnum = new ArrayList<Integer>();
int data;
Scanner in = new Scanner(System.in);
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 == 0)
{
oddnum.add(num1.get(i));
}
}
b)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> oddnum = new ArrayList<Integer>();
int data;
Scanner in = new Scanner(System.in);
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 != 0)
{
oddnum.add(num1.get(i));
}
}
c)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> oddnum = new ArrayList<Integer>();
int data;
Scanner in = new Scanner(System.in);
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 == 0)
{
oddnum.add(num1[i]);
}
}
d)
ArrayList<Integer> num1;
ArrayList<Integer> oddnum = new ArrayList<Integer>();
int data;
Scanner in = new Scanner(System.in);
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1[i] % 2 != 0)
{
oddnum.add(num1[i]);
}
}
Title: Which code snippet fills one integer array list and stores its odd integers in another array list?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
42) Is there any thing wrong with the following code snippet?
String[] data = { "abc", "def", "ghi", "jkl" };
String searchedValue = "ghi";
int pos = 0;
boolean found = false;
while (pos < data.length)
{
if (data[pos].equals(searchedValue))
{
found = true;
}
else
{
found = false;
}
pos++;
}
if (found)
{
System.out.println("Found at position: " + pos);
}
else
{
System.out.println("Not found");
}
a) There is nothing wrong.
b) There is compile-time error.
c) There is a bounds error.
d) There is a logic error.
Title: Is there any thing wrong with array search code?
Difficulty: Hard
Section Reference 1: 7.3 Common Array Algorithms
43) Consider the following code snippet:
String[] data = { "abc", "def", "ghi", "jkl" };
String [] data2;
In Java 6 and later, which statement copies the data array to the data2 array?
a) data2 = Arrays.copyOf(data, data2.length);
b) data2 = Arrays.copyOf(data, data.length);
c) data2 = Arrays.copyOf(data, data.size());
d) data2 = Arrays.copyOf(data);
Title: Which code is correct to copy from one array to another?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
44) Consider the following code snippet in Java 6 or later:
String[] data = { "abc", "def", "ghi", "jkl" };
String[] data2 = Arrays.copyOf(data, data.length - 1);
What does the last element of data2 contain?
a) "abc"
b) "def"
c) "ghi"
d) "jkl"
Title: What does the last element of data2 contain after an array copy?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
45) Consider the following code snippet:
String[] data = { "abc", "def", "ghi", "jkl" };
Using Java 6 or later, which statement grows the data array to twice its size?
a) data = Arrays.copyOf(data, 2 * data.length);
b) data = Arrays.copyOf(data, 2);
c) data = Arrays.copyOf(data, 2 * data);
d) data = Arrays.copyOf(data, 2 * data.size());
Title: Which code is correct to grow the size of an array?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
45) Consider the following code snippet:
String[] data = { "123", "ghi", "jkl", "def", "%&*" };
Which statement sorts the data array in ascending order?
a) data = Arrays.sort();
b) Arrays.sort(data);
c) data = Arrays.sort(data.length);
d) data = Arrays.sort(data);
Title: Which code is correct to sort an array?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
46) Which one of the following statements is true about passing arrays to a method?
a) By default, arrays are passed by value to a method
b) Arrays, when updated in a called method, are not reflected to the calling method
c) By default, arrays are passed by reference to a method
d) Arrays are passed only if size is specified as another argument
Title: Which statement is true about passing arrays to a method?
Difficulty: Easy
Learning Objective 1: LO 6.4 Implement methods that process arrays.
Section Reference 1: 7.3 Common Array Algorithms
47) Which one of the following is the correct header for a method named arrMeth that is called like this:
arrMeth(intArray); // intArray is an integer array of size 3
a) public static void arrMeth(int[] ar, int n)
b) public static void arrMeth(r[], n)
c) public static void arrMeth(int n , int[] ar)
d) public static void arrMeth(int[] ar)
Title: Which method header is valid for the method called in this snippet?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
48) Why is the following method header invalid?
public static int[5] meth(int[] arr, int[] num)
a) Methods that return an array cannot specify its size
b) Methods cannot have an array as a return type
c) Methods cannot have an array as a parameter variable
d) Methods cannot have two array parameter variables
Title: Why is the following method signature invalid?
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
49) What is the output of the following code snippet?
public static void main(String[] args)
{
String[] arr = { "aaa", "bbb", "ccc" };
mystery(arr);
System.out.println(arr[0] + " " + arr.length);
}
public static void mystery(String[] arr)
{
arr = new String[5];
arr[0] = "ddd";
}
a) ddd 5
b) ddd 3
c) aaa 5
d) aaa 3
Title: What is the output after method call that modifies array parameter variable
Difficulty: Hard
Section Reference 1: 7.3 Common Array Algorithims
50) Consider the following code snippet. Which statement should be used to fill in the empty line so that the output will be [32, 54, 67.5, 29, 35]?
public static void main(String[] args)
{
double data[] = {32, 54, 67.5, 29, 35};
______________
System.out.println(str);
}
a) String str = Arrays.format(data);
b) String str = data.toString();
c) String str = Arrays.toString(data);
d) String str = str + ", " + data[i];
Title: What statement provides the desired output string from array
Difficulty: Hard
Section Reference 1: 7.3 Common Array Algorithms
51) Select the statement that reveals the logic error in the following method.
public static double minimum(double[] data)
{
double smallest = 0.0;
for (int i = 0; i < data.length; i++)
{
if (data[i] < smallest)
{
smallest = data[i];
}
}
return smallest;
}
a) double m = minimum(new double[] { 1.2, -3.5, 6.6, 2.4 });
b) double m = minimum(new double[] { 1.2, 23.5, 16.6, -23.4 });
c) double m = minimum(new double[] { -10.2, 3.5, 62.6, 21.4 });
d) double m = minimum(new double[] { 12.2, 31.5, 6.6, 2.4 });
Title: What statement reveals the logic error of a method using array
Difficulty: Hard
Section Reference 1: 7.3 Common Array Algorithims
52) Consider the following 2-dimensional array. Select the statement that gives the number of columns in the third row.
int[][] counts =
{
{ 0, 0, 1 },
{ 0, 1, 1, 2 },
{ 0, 0, 1, 4, 5 },
{ 0, 2 }
};
a) int cols = counts[2].size();
b) int cols = counts.length[2];
c) int cols = counts.length;
d) int cols = counts[2].length;
Title: What statement gives the column size of a 2-dimensional array
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
53) Consider the following code snippet:
int cnt = 0;
int[][] numarray = new int[2][3];
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 2; j++)
{
numarray[j][i] = cnt;
cnt++;
}
}
What is the value of numarray[1][2] after the code snippet is executed?
a) 2
b) 5
c) 3
d) 4
Title: What is the value of this 2-dimension array element after the nested for loop is executed?
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
54) How many elements can be stored in an array of dimension 2 by 3?
a) 2
b) 3
c) 5
d) 6
Title: How many elements can be stored in an array of dimension 2 by 3?
Difficulty: Easy
Section Reference 1: 7.6 Two-Dimensional Arrays
55) Which one of the following statements is the correct definition for a two-dimensional array of 20 rows and 2 columns of the type integer?
a) int[][] num = new int[20][2];
b) int[][] num = new int[2][20];
c) int[][] num = new int[20,2];
d) int[][] num = new int[2,20];
Title: Which is correct definition for a 2D integer array of 20 rows and 2 columns?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
56) Consider the following code snippet:
int[][] numarray =
{
{ 3, 2, 3 },
{ 0, 0, 0 }
};
System.out.print(numarray[0][0]);
System.out.print(numarray[1][0]);
What is the output of the given code snippet?
a) 00
b) 31
c) 30
d) 03
Title: What is output of snippet that initializes 2-dimensional array and displays two of its elements?
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
57) Which one of the following is the correct definition for initializing data in a two-dimensional array of three rows and two columns?
a)
int[][] arr =
{
{ 1, 1, 1 },
{ 2, 2, 2 },
};
b)
int[][] arr =
{
{ 1, 1 },
{ 2, 2 },
{ 3, 3 }
};
c)
int[][] arr =
{
{ 1, 1 }
{ 2, 2 }
{ 3, 3 }
};
d)
int[][] arr =
{
{ 1, 1, 1 }
{ 2, 2, 2 }
{ 3, 3, 3 }
};
Title: Which is correct definition for initializing a 2-dimensional array of three rows and two columns?
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
58) Which one of the following statements is correct for displaying the value in the second row and the third column of a two-dimensional, size 3 by 4 array?
a) System.out.println(arr[1][2]);
b) System.out.println(arr[2][3]);
c) System.out.println(arr[2][1]);
d) System.out.println(arr[3][2]);
Title: Which statement displays the value in the second row and third column of a 2-dimensional 3 by 4 array?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
59) Consider the following code snippet:
int[][] arr =
{
{ 13, 23, 33 },
{ 14, 24, 34 }
};
Identify the appropriate statement to display the value 24 from the given array?
a) System.out.println(arr[1][2]);
b) System.out.println(arr[2][2]);
c) System.out.println(arr[1][1]);
d) System.out.println(arr[2][1]);
Title: Which statement displays the value 24 from the 2-dimensional array initialized here?
Difficulty: Easy
Section Reference 1: 7.6 Two-Dimensional Arrays
60) Consider the following code snippet:
int val = arr[0][2];
Which value of arr is stored in the val variable?
a) The value in the first row and the second column
b) The value in the first row and the first column
c) The value in the first row and the third column
d) The value in the third row and the second column
Title: Which value of the 2-dimensional array arr is stored in arr[0][2]?
Difficulty: Easy
Section Reference 1: 7.6 Two-Dimensional Arrays
61) Consider the following code snippet:
int[][] arr =
{
{ 1, 2, 3 },
{ 4, 5, 6 }
};
int val = arr[0][2] + arr[1][2];
System.out.println(val);
What is the output of the given code snippet on execution?
a) 5
b) 7
c) 9
d) 10
Title: What is the output of this snippet that sums two values in a 2-dimensional array?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
62) Which one of the following is a valid signature of a method with an integer two-dimensional array parameter of size 10 x 10?
a) public static void func(int[][] arr)
b) public static void func(int[10][] arr)
c) public static void func(int[][10] arr)
d) public static void func(int[10][10] arr)
Title: Which signature is valid for a method with a 2-dimensional array parameter of size 10 x 10?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
63) Consider the following code snippet:
ArrayList<Integer> num1 = new ArrayList<Integer>();
int data;
Scanner in = new Scanner(System.in);
for (int i = 0; i < 5; i++)
{
data = in.nextInt();
num1.add(data);
if (data == 0 && num1.size() > 3)
{
num1.remove(num1.size() - 1);
}
}
System.out.println("size is : " + num1.size());
What is the output of the given code snippet if the user enters 1,2,0,0,1 as the input?
a) size is : 1
b) size is : 2
c) size is : 4
d) size is : 0
Title: What is the size of the array list after for loop with given input values?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
64) Which one of the following statements about declaring an array list as a method parameter is true?
a) An array list declared as a method parameter should be accompanied with its size.
b) An array list declared as a method parameter is a constant value by default.
c) An array list value cannot be modified in a method when the array list is declared as a parameter.
d) An array list value can be modified inside the method.
Title: Which statement is true about declaring an array list as a method parameter?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
65) Which one of the following is a correct declaration for a method named passAList with the array list num of size 5 as a parameter?
a) public static void passAList(ArrayList<Integer> num[5])
b) public static void passAList(ArrayList<Integer> num, 5)
c) public static void passAList(ArrayList<Integer> num)
d) public static void passAList(num)
Title: Which correctly declares a method with an array listof size 5 as a parameter?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
66) Consider the following code snippet:
public static void check(ArrayList<Integer> chknum1)
{
int cnt = 0;
for(int i = 0; i < chknum1.size(); i++)
{
if(chknum1.get(i) == 0)
{
cnt++;
}
}
System.out.println("The total 0 values in the list are: " + cnt);
}
Which one of the following is true about the check method in the given code snippet?
a) The check method counts all the elements with value 0 in an array list passed as a parameter to the method.
b) The check method removes all the elements with value 0 from an array list passed as a parameter to the method.
c) The check method counts all the elements with value 0 in an array list passed as a parameter to a method and also returns the count.
d) The check method adds 0 to the elements of an array list as a parameter to a method and also returns the array list.
Title: Which is true about the check method in the given code snippet?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
67) Consider the following line of code for calling a method named func1:
func1(listData, varData);
Which one of the following method headers is valid for func1, where listData is an integer array list and varData is an integer variable?
a) public static void func1(int[] listData, int varData)
b) public static void func1(ArrayList<Integer> listData, varData)
c) public static void func1(ArrayList<Integer> ldata, int vdata)
d) public static void func1(int vdata, ArrayList<Integer> ldata)
Title: Which method header is valid for the method called in this snippet?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
68) What is the output of the following code snippet?
public static int check(ArrayList<Integer> listData)
{
int sum = 0;
for (int i = 0; i < listData.size(); i++)
{
sum = sum + listData.get(i);
}
return sum;
}
public static void main(String[] args)
{
ArrayList<Integer> vdata = new ArrayList<Integer>();
int rsum;
for (int cnt = 0; cnt < 3; cnt++)
{
vdata.add(cnt + 1);
}
rsum = check(vdata);
System.out.println(rsum);
}
a) 4
b) 2
c) 3
d) 6
Title: What is the output of this code that calls a method with an array list parameter?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
69) What is the result of the following definition of an array list?
ArrayList<Double> points;
a) The statement causes a compile time error as the size of the array list is not defined.
b) The statement creates an array list of size 0.
c) The statement creates an array list with unlimited size.
d) The statement defines an array list reference but does not create an array list.
Title: What is the result of this definition of an array list?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
70) Consider the following code snippet:
ArrayList<Double> somedata = new ArrayList<Double>();
somedata.add(10.5);
What is the size of the array list somedata after the given code snippet is executed?
a) 0
b) 1
c) 10
d) 2
Title: What is the size of the given array list after add(10.5)?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
71) What is the output of the following code snippet?
ArrayList<Integer> num;
num.add(4);
System.out.println(num.size());
a) 1
b) 0
c) 4
d) Error because num is not initialized
Title: What is value of array list.size after this snippet with add()?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
72) Your program needs to store an integer sequence of unknown length. Which of the following is most suitable to use?
a) An array declared as int[] marks;
b) A array list declared as ArrayList<Integer> marks = new ArrayList<Integer>();
c) An array declared as int marks[10000];
d) An array declared as int marks[10];
Title: Which can you use to store a sequence of integers of unknown length?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
73) Consider the following code snippet:
ArrayList<Integer> arrList = new ArrayList<Integer>();
for (int i = 0; i < arrList.size(); i++)
{
arrList.add(i + 3);
}
What value is stored in the element of the array list at index 0?
a) 0
b) 3
c) 6
d) None
Title: What value is stored in array list after this for loop initializes the array list?
Difficulty: Hard
Section Reference 1: 7.7 Array Lists
74) What should you check for when calculating the largest value in an array list?
a) The array list contains at least one element.
b) The array list contains at least two elements.
c) The array list contains the minimum value in the first element.
d) The array list contains the maximum value in the first element.
Title: What should be ensured for calculating the largest value in an array list?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
75) Which one of the following is the correct code snippet for calculating the largest value in an integer array list arrList of size 10?
a)
int maximum = 0;
for (int counter = 1; counter < arrList.size(); counter++)
{
if (arrList.get(counter) > maximum)
{
maximum = arrList.get(counter);
}
}
b)
int maximum = arrList.get(0);
for (int counter = 1; counter < arrList.size(); counter++)
{
if (arrList.get(counter) > maximum)
{
maximum = arrList.get(counter);
}
}
c)
int maximum = arrList.get(1);
for (int counter = 1; counter < arrList.size(); counter++)
{
if (arrList.get(counter) > maximum)
{
maximum = arrList.get(counter);
}
}
d)
int maximum = arrList.get(0);
for (int counter = 1; counter > arrList.size(); counter++)
{
if (arrList.get(counter) < maximum)
{
maximum = arrList.get(counter);
}
}
Title: Which is correct code for calculating the largest value in array list of size 10?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
76) What is the value of the cnt variable after the execution of the code snippet below?
ArrayList<Integer> somenum = new ArrayList<Integer>();
somenum.add(1);
somenum.add(2);
somenum.add(1);
int cnt = 0;
for (int index = 0; index < somenum.size(); index++)
{
if (somenum.get(index) % 2 == 0)
{
cnt++;
}
}
a) 1
b) 2
c) 3
d) 0
Title: What is value of cnt variable after this for loop traverses the array list?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
77) Which one of the following code snippets accepts the integer input in an array list named num1 and stores the even integers of num1 in another array list named evennum?
a)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> evennum = new ArrayList<Integer>();
Scanner in = new Scanner(System.in);
int data;
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 == 0)
{
evennum.add(num1.get(i));
}
}
b)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> evennum = new ArrayList<Integer>();
Scanner in = new Scanner(System.in);
int data;
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 != 0)
{
evennum.add(num1.get(i));
}
}
c)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> evennum = new ArrayList<Integer>();
Scanner in = new Scanner(System.in);
int data;
for int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 != 0)
{
evennum[i] = num1[i];
}
}
d)
ArrayList<Integer> num1 = new ArrayList<Integer>();
ArrayList<Integer> evennum = new ArrayList<Integer>();
Scanner in = new Scanner(System.in);
int data;
for (int i = 0; i < 10; i++)
{
data = in.nextInt();
num1.add(data);
if (num1.get(i) % 2 == 0)
{
evennum[i] = num1[i];
}
}
Title: Which code snippet fills one integer array and stores its even integers in another array?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
78) Which one of the following is a correct declaration for a method named passAList that has as arguments an array list myList of size 10 and an integer array intArr of size 20, and that modifies the contents of myList and intArr?
a) public static void passAList(ArrayList<Integer> myList(10), int[] intArr)
b) public static void passAList(ArrayList<Integer> myList, int[20] intArr)
c) public static void passAList(ArrayList<Integer> myList, int[] intArr)
d) public static void passAList(ArryaList<Integer> myList, int intArr)
Title: Which correctly declares a method that can modify the contents of its array list and array parameter of size 10?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
79) What is the value of myArray[1][2] after this code snippet is executed?
int count = 0;
int[][] myArray = new int[4][5];
for (int i = 0; i < 5; i++)
{
for (int j = 0; j < 4; j++)
{
myArray[j][i] = count;
count++;
}
}
a) 8
b) 9
c) 19
d) 11
Title: What is the value of this 2-dimensional array element after the nested for loop is executed?
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
80) How many elements can be stored in a two-dimensional 5 by 6 array?
a) 5
b) 6
c) 11
d) 30
Title: How many elements can be stored in an array of dimension 5 by 6?
Difficulty: Easy
Section Reference 1: 6.7 Two-Dimensional Arrays
81) What is the output of the code snippet below?
int[][] numarray =
{
{ 8, 7, 6 },
{ 0, 0, 0 }
};
System.out.print(numarray[0][0]);
System.out.print(numarray[1][0]);
a) 00
b) 87
c) 80
d) 08
Title: What is output of snippet that initializes 2-dimensional array and displays two of its elements?
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
82) Which one of the following statements is correct for displaying the value in the third row and the fourth column of a two-dimensional 5 by 6 array?
a) System.out.println(arr[2][3]);
b) System.out.println(arr[3][4]);
c) System.out.println(arr[3][2]);
d) System.out.println(arr[4][3]);
Title: Which statement displays the value in the second row and third column of a 2-dimensional 5 by 6 array?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
83) What is the output of the code snippet below?
int[][] arr =
{
{ 1, 2, 3, 0 },
{ 4, 5, 6, 0 },
{ 0, 0, 0, 0 }
};
int val = arr[1][2] + arr[1][3];
System.out.println(val);
a) 5
b) 6
c) 7
d) 9
Title: What is the output of this snippet that sums two values in a 2-dimensional array?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
84) Consider the following code snippet:
int[][] arr =
{
{ 1, 2, 3, 0 },
{ 4, 5, 6, 0 },
{ 0, 0, 0, 0 }
};
int[][] arr2 = arr;
System.out.println(arr2[2][1] + arr2[1][2]);
What is the output of the given code snippet on execution?
a) 5
b) 6
c) 7
d) 9
Title: What is the output of this snippet that sums two values in a copied 2-dimensional array reference?
Difficulty: Medium
Section Reference 1: 7.6 Two-Dimensional Arrays
85) Which statement is true about the code snippet below?
ArrayList<String> names = new ArrayList<String>();
names.add("John");
names.add("Jerry");
ArrayList<String> friends = names;
friends.add("Harry");
a) The final size of names is 2; the final size of friends is 3
b) The final size of names is 3; the final size of friends is 2
c) The final size of names is 3; the final size of friends is 3
d) Compilation error
Title: What’s true about code that copies array list reference
Difficulty: Hard
Section Reference 1: 7.7 Array Lists
86) Which statement is true about the code snippet below?
ArrayList<String> names = new ArrayList<String>();
names.add("John");
names.add("Jerry");
ArrayList<String> friends = new ArrayList<String>(names);
friends.add("Harry");
a) The final size of names is 2; the final size of friends is 3
b) The final size of names is 3; the final size of friends is 2
c) The final size of names is 3; the final size of friends is 3
d) Compilation error
Title: What’s true about code that copies array list
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
87) Consider the following code snippet:
public static void main(String[] args)
{
ArrayList<String> names = new ArrayList<String>();
names.add("John");
names.add("Jerry");
names.add("Janet");
ArrayList<String> names2 = reverse(names);
}
public static ArrayList<String> reverse(ArrayList<String> names)
{
ArrayList<String> result = new ArrayList<String>();
for (int i = names.size() - 1; i >= 0; i--)
{
result.add(names.get(i));
}
return <String>result;
}
Which statement is true after the main method is executed?
a) names contains "Janet", "Jerry", "John" in this order
b) names contains "John", "Jerry", "Janet" in this order
c) reverse method has a bound error
d) Compilation error due to the return statement in reverse method
Title: What’s true about method that has array list as parameter and returns array list
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
88) Which statement is true about the code snippet below?
public static void main(String[] args)
{
Scanner in = new Scanner(System.in);
ArrayList<Double> inputs = new ArrayList<Double>();
int ind = 0;
while (in.hasNextDouble())
{
inputs.set(ind, in.nextDouble());
ind++;
}
}
a) The code adds all input numbers to the array list
b) The code has compile-time error
c) The array list is full after 100 numbers are entered
d) The code has a run-time error
Title: What’s true about code that adds input data to array list
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
89) Which statement is true about the code snippet below?
ArrayList<String> names = new ArrayList<String>();
names.add("John");
names.add("Jerry");
ArrayList<String> friends = new ArrayList<String>(names);
names.add("Harry");
a) The final size of names is 2; the final size of friends is 3
b) The final size of names is 3; the final size of friends is 2
c) The final size of names is 3; the final size of friends is 3
d) Compilation error
Title: What's true about code that copies array list
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
90) When an integer literal is added to an array list declared as ArrayList<Integer>, Java performs:
a) casting
b) trimming
c) auto-boxing
d) auto-fixing
Title: Java performs _____ when adding primitive types to array list
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
91) What is the output of the following statements?
ArrayList<String> names = new ArrayList<String>();
names.add("Bob");
names.add(0, "Ann");
names.remove(1);
names.add("Cal");
names.set(1, "Tony");
for (String s : names)
{
System.out.print(s + ", ");
}
a) Cal, Bob, Ann
b) Ann, Bob
c) Ann, Tony
d) Cal, Bob, Tony
Title: What is the output after array list has add, remove, set applied
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
92) What is the output of the following statements?
ArrayList<String> names = new ArrayList<String>();
names.add("Bob");
names.add(0, "Ann");
names.remove(1);
names.add("Cal");
names.set(2, "Tony");
for (String s : names)
{
System.out.print(s + ", ");
}
a) Cal, Bob, Ann
b) Ann, Bob
c) Ann, Cal, Tony
d) Array list bound error
Title: What is the output after array list has add, remove, set applied
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
93) What is the output of the following statements?
ArrayList<String> cityList = new ArrayList<String>();
cityList.add("London");
cityList.add("New York");
cityList.add("Paris");
cityList.add("Toronto");
cityList.add("Hong Kong");
cityList.add("Singapore");
System.out.print(cityList.size());
System.out.print(" " + cityList.contains("Toronto"));
System.out.print(" " + cityList.indexOf("New York"));
System.out.println(" " + cityList.isEmpty());
a) 5 true 1 false
b) 6 true 2 false
c) 5 false 1 false
d) 6 true 1 false
Title: What is the output after array list has add, size, contains, indexOf, isEmpty applied
Difficulty: Hard
Section Reference 1: 7.7 Array Lists
94) What should you check for when calculating the smallest value in an array list?
a) The array list contains at least one element.
b) The array list contains at least two elements.
c) The array list contains the maximum value in the first element.
d) The array list contains the minimum value in the first element.
Title: What should be checked when calculating the smallest value in an array list?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
95) Which one of the following is the correct code snippet for calculating the largest value in an integer array list aList?
a)
int max = 0;
for (int count = 1; count < aList.size(); count++)
{
if (aList.get(count) > max)
{
max = aList.get(count);
}
}
b)
int max = aList.get(0);
for (int count = 1; count < aList.size(); count++)
{
if (aList.get(count) > max)
{
max = aList.get(count);
}
}
c)
int max = aList[1];
for (int count = 1; count < aList.size(); count++)
{
if (aList.get(count) > max)
{
max = aList.get(count);
}
}
d)
int max = aList.get(0);
for (int count = 1; count > aList.size(); count++)
{
if (aList.get(count) >= max)
{
max = aList.get(count);
}
}
Title: Which is correct code for calculating the largest value in array list of size 6?
Difficulty: Medium
Section Reference 1: 7.7 Array Lists
96) Consider the following code snippet, where the array lists contain elements that are stored in ascending order:
ArrayList<Integer> list1 = new ArrayList<Integer>();
ArrayList<Integer> list2 = new ArrayList<Integer>();
. . .
int count = 0;
for (int i = 0; i < list1.size() && i < list2.size(); i++)
{
if (list1.get(i) == list2.get(i))
{
count++;
}
}
Which one of the following descriptions is correct for the given code snippet?
a) The code snippet finds the highest value out of the two array lists.
b) The code snippet finds the lowest value out of the two array lists.
c) The code snippet compares the values of two array lists and stores the count of total matches found.
d) The code snippet adds the values of the two array lists.
Title: Which description is correct for this for loop that processes two array lists?
Difficulty: Easy
Section Reference 1: 7.7 Array Lists
97) What is the output of the following code?
int[][] counts =
{
{ 0, 0, 1 },
{ 0, 1, 1, 2 },
{ 0, 0, 1, 4, 5 },
{ 0, 2 }
};
System.out.println(counts[3].length);
a) 2
b) 3
c) 4
d) 5
Title: What is the output of the code with a 2-dimensional array having different column sizes
Difficulty: Hard
Section Reference 1: 7.6 Two-Dimensional Arrays
98) Assume the following variable has been declared and given a value as shown:
int[] numbers = {9, 17, -4, 21 };
Which is the value of numbers.length?
a)3
b)4
c)9
d)21
Title: Which is the value of numbers.length
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
99) Assume the variable numbers has been declared to be an array that has at least one element. Which is the following represents the last element in numbers?
a)numbers[numbers.length]
b)numbers.length
c)numbers[–1]
d)numbers[numbers.length – 1]
Title: Which is the following represents the last element in numbers
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
100) What will be printed by the statements below?
int[] values = { 1, 2, 3, 4};
values[2] = 24;
values[values[0]] = 86;
for (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");
a)86 2 24 4
b)86 24 3 4
c)1 86 24 4
d)1 2 24 86
Title: What will be printed by the statements below
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
101) What will be printed by the statements below?
int[] values = { 10, 20, 30, 7};
int[] numbers = values;
numbers[2] = 24;
values[3] = numbers[0] + 6;
System.out.println (numbers[2] + " " + numbers[3] + " "
+ values[2] + " " + values[3]);
a)24 0 30 16
b)24 0 30 6
c)24 7 30 16
d)24 16 24 16
Title: What will be printed by the statements below
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
102) The integer array numbers will be filled with the values from the Scanner in. If there are more input values than there are spaces in the array, only enough values to fill the array should be read. The integer variable currentSize should be set to the number of values read. Partial code to do this is given below:
int[] numbers; // Assume it is created with at least 1 space
Scanner in = new Scanner (System.in);
int currentSize = 0;
while (/* Put condition here */)
{
int value = in.nextInt();
numbers[currentSize] = value;
currentSize++;
}
What condition will complete this code?
a)currentSize < numbers.length && in.hasNextInt()
b)currentSize < numbers.length || in.hasNextInt()
c)currentSize <= numbers.length && in.hasNextInt()
d)currentSize <= numbers.length || in.hasNextInt()
Title: What condition will complete this code
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
103) The method findLargest should return the largest of any number of double values. For example, the call findLargest (3.4, -2.6, 2.9) should return 3.4 and the call findLargest (9.2, 17.6, 3.4, -2.6, 2.9) should return 17.6. Partial code to do this is given below:
double findLargest (double... values)
{
double max = values[0];
// New code goes here
return max;
}
What code will complete this method?
- for (double val: values)
{
if (val > max)
max = val;
}
- for (int i = 1; i < values.length; i++)
{
if (i > max)
max = i;
}
- for (double val: values)
{
if (values[val] > max)
max = values[val];
}
- for (int i = 1; i < values.length; i++)
{
if (values[i] > max)
max = i;
}
Title: What condition will complete this code
Difficulty: Medium
Section Reference 1: 7.3 Common Array Algorithms
104) Assume the array of integers values has been created and process is a method that has a single integer parameter. Which of the following is equivalent to the loop below?
for (int val: values)
{
process (val);
}
a)for (int i = 0; i < values.length; i++)
{
process (values[i]);
}
b)for (int i = 1; i <= values.length; i++)
{
int val = values[i];
process (val);
}
c) for (int i = 0; i < values.length; i++)
{
int val = values[i];
process (val);
}
d)for (int i = 0; i < values.length; i++)
{
process (i);
}
Title: Which of the following is equivalent to the loop below
Difficulty: Medium
Section Reference 1: 7.2 The Enhanced for Loop
105) Assume the array of integers values has been created. Which condition must be used in the indicated area so the loop below will assign max the largest value in values?
int max = values[0];
for (int val: values)
{
if (/* Put condition here */)
max = val;
}
a)max > val
b)val > max
c)values[val] > max
d)max > values[val]
Title: Which condition must be used in the indicated area so the loop below will assign max the largest value in values
Difficulty: Medium
Section Reference 1: 7.2 The Enhanced for Loop
106) Assume the array of integers values has been created. Which condition must be used in the indicated area so the loop below will assign max the largest value in values?
int max = values[0];
for (int current = 1; current < values.length; current++)
{
if (/* Put condition here */)
max = values[current];
}
a)current > max
b)max > current
c)max > values[current]
d)values[current] > max
Title: Which condition must be used in the indicated area so the loop below will assign max the largest value in values
Difficulty: Medium
Section Reference 1: 7.2 The Enhanced for Loop
107) What will be printed by the statements below?
int[] values = { 10, 20, 30, 40};
for (int i = 1; i < values.length; i++)
values[i] = values[i – 1];
for (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");
a)10 9 8 7
b)10 19 29 39
c)10 10 10 10
d)9 19 29 39
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
108) What will be printed by the statements below?
int[] values = { 4, 5, 6, 7};
for (int i = 1; i < values.length; i++)
values[i] = values[i – 1] + values[i];
for (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");
a)4 9 11 13
b)4 9 15 22
c)9 11 13 7
d)4 5 6 7
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
109) What will be printed by the statements below?
int[] values = { 4, 5, 6, 7};
values[0] = values[3];
values[3] = values[0];
for (int i = 0; i < values.length; i++)
System.out.print (values[i] + " ");
a)7 5 6 4
b)7 6 5 4
c)7 5 6 7
d)4 5 6 4
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
110) What will be printed by the statements below?
int[] values = { 10, 24, 3, 64};
int position = 0;
for (int i = 1; i < values.length; i++)
if (values[i] > values[position])
position = i;
System.out.print (position);
a)0
b)1
c)2
d)3
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
111) Assume the method createSomething has been defined as follows:
int [] createSomething (int start, int size)
{
int [] result = new int[size];
for (int i = 0; i < result.length; i++)
{
result[i] = start;
start++;
}
return result;
}
What is printed by the statement below?
System.out.print (Arrays.toString(createSomething(4, 3)));
a)[3, 4, 5, 6]
b)[4, 4, 4]
c)[3, 3, 3, 3]
d)[4, 5, 6]
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
112) Assume the method doSomething has been defined as follows:
int [] doSomething (int[] values)
{
int [] result = new int[values.length - 1];
for (int i = 0; i < result.length; i++)
{
result[i] = values[i] + values[i + 1];
}
return result;
}
What is printed by the statements below?
int [] nums = {3, 18, 29, -2} ;
System.out.print (Arrays.toString(doSomething(nums)));
a)[4, 19, 30, -1]
b)[21, 47, 27]
c)[21, 50, 48]
d)[3, 21, 47, 27]
Title: What will be printed by the statements below
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
113) Assume the following variable has been declared and given a value as shown:
int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data.length?
a)4
b)3
c)12
d)6
Title: Which is the value of data.length
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
114) Assume the following variable has been declared and given a value as shown:
int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data[0].length?
a)21
b)12
c)4
d)3
Title: Which is the value of data[0].length
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
115) Assume the following variable has been declared and given a value as shown:
int[][] data = {
{9, 17, -4, 21 },
{15, 24, 0, 9},
{6, 2, -56, 8},
};
Which is the value of data[1][2]?
a)0
b)17
c)15
d)-56
Title: Which is the value of data[1][2]
Section Reference 1: 7.6 Two-Dimensional Arrays
Difficulty: Medium
116) What will be printed by the statements below?
ArrayList<String> names = new ArrayList<String>();
names.add("Annie");
names.add("Bob");
names.add("Charles");
names.set(2, "Doug");
names.add(0, "Evelyn");
System.out.print (names);
a)[Annie, Bob, Charles, Doug, Evelyn]
b)[Evelyn, Annie, Bob, Doug]
c)[Evelyn, Doug, Charles]
d)[Evelyn, Annie, Doug, Charles]
Title: What will be printed by the statements below
Section Reference 1: 7.7 Array Lists
Difficulty: Medium
117) What will be printed by the statements below?
ArrayList<String> names = new ArrayList<String>();
names.add("Annie");
names.add("Bob");
names.add("Charles");
for (int i = 0; i < 3; i++)
{
String extra = names.get(i);
names.add (extra);
}
System.out.print (names);
a)[Annie, Bob, Charles, Annie, Bob, Charles]
b)[Annie, Bob, Charles, Charles, Bob, Annie]
c)[Annie, Annie, Bob, Bob, Charles, Charles]
d)[Annie, Bob, Charles, Bob, Charles]
Title: What will be printed by the statements below
Section Reference 1: 7.7 Array Lists
Difficulty: Medium