Deck 9: Strings

Question 1

How many elements are in array double[] list = new double[5]? B. 4
C) 6
D) 0

Answer 1

A

Question 2

In Java, the word true is ________. B. a Java keyword
C) same as value 0
D) same as value 1

Answer 2

A

Question 3

How many times will the following code print "Welcome to Java"? int count = 0;
Do {
System.out.println("Welcome to Java");
} while (count++ < 10);

A) 10
B) 8
C) 0
D) 9

Answer 3

E

Question 4

24 % 5 is _____ A. 2
B) 0
D) 1
E) 3

Question 5

The "less than or equal to" comparison operator in Java is __________. A. <<
B) =<
C) !=
E) <

Question 6

What is the result of 45 / 4? B. 12
C) 10
D) 11.25

Question 7

Write the following method that returns true if the list is already sorted in increasing order.
public static boolean isSorted(int[] list)
Write a test program that prompts the user to enter a list and displays whether the list is sorted or not. Here is a sample run. Note that the first number in the input indicates the number of the elements in the list.

Enter list: 8 10 1 5 16 61 9 11 1
The list is not sorted

Enter list: 10 1 1 3 4 4 5 7 9 11 21
The list is already sorted

Here is the outline of the program:
public class Test {
public static void main(String[] args) {
// Fill in the code here
}
public static boolean isSorted(int[] list) {
// Fill in the code here
}
}

Question 8

Analyze the following code: public class Test {
Public static void main(String[] args) {
System.out.println(xMethod(5, 500L));
}
Public static int xMethod(int n, long l) {
System.out.println("int, long");
Return n;
}
Public static long xMethod(long n, long l) {
System.out.println("long, long");
Return n;
}
}

A) The program does not compile because the compiler cannot distinguish which xmethod to invoke.
B) The program runs fine but displays things other than 5.
C) The program displays long, long followed by 5.
D) The program displays int, long followed by 5.

Question 9

What is the value in count after the following loop is executed? int count = 0;
Do {
System.out.println("Welcome to Java");
} while (count++ < 9);
System.out.println(count);

A) 11
B) 0
C) 9
D) 8

Question 10

If you attempt to add an int, a byte, a long, and a double, the result will be a __________ value. A. int
B) long
C) byte
D) double

Question 11

What is i after the following for loop? int y = 0;
For (int i = 0; i<10; ++i) {
Y += i;
}

A) 9
B) 10
D) 11

Question 12

What is the number of iterations in the following loop: for (int i = 1; i <= n; i++) {
// iteration
}

A) 2*n
C) n - 1
D) n + 1

Question 13

Write a method to display a pattern as follows:
1
1 2
1 2 3
...
...
1 2 3 4 5 ... n
The method header is
public static void displayPattern(int n)
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Enter the side of the pentagon
System.out.print("Enter n: ");
int n = input.nextInt();
displayPattern(n);
}
public static void displayPattern(int n) {
// Fill in the code here
}
}

Question 14

What is Math.floor(3.6)? A. 5.0
B) 3
D) 4

Question 15

Analyze the following code. public class Test {
Public static void main(String[] args) {
System.out.println(max(1, 2));
}
Public static double max(int num1, double num2) {
System.out.println("max(int, double) is invoked");
If (num1 > num2)
Return num1;
Else
Return num2;
}
Public static double max(double num1, int num2) {
System.out.println("max(double, int) is invoked");
If (num1 > num2)
Return num1;
Else
Return num2;
}
}

A) The program runs and prints 2 followed by "max(double, int)" is invoked.
B) The program cannot compile because the compiler cannot determine which max method should be invoked.
C) The program runs and prints "max(int, double) is invoked" followed by 2.
D) The program runs and prints 2 followed by "max(int, double)" is invoked.
E) The program cannot compile because you cannot have the print statement in a non-void method.

Question 16

__________ is to implement one method in the structure chart at a time from the top to the bottom. A. Stepwise refinement
C) Bottom-up and top-down approach
D) Bottom-up approach

Question 17

What is the output for y? int y = 0;
For (int i = 0; i<10; ++i) {
Y += i;
}
System.out.println(y);
B) 12
C) 13
D) 10
E) 11

Question 18

The following code displays ___________. double temperature = 50;
If (temperature >= 100)
System.out.println("too hot");
Else if (temperature <= 40)
System.out.println("too cold");
Else
System.out.println("just right");

A) too hot
B) too cold
C) too hot too cold just right

Question 19

Analyze the following code fragments that assign a boolean value to the variable even. Code 1:
If (number % 2 == 0)
Even = true;
Else
Even = false;
Code 2:
Even = (number % 2 == 0) ? true: false;
Code 3:
Even = number % 2 == 0;

A) Code 3 has a syntax error, because you attempt to assign number to even.
B) Code 2 has a syntax error, because you cannot have true and false literals in the conditional expression.
C) All three are correct, but Code 1 is preferred.
D) All three are correct, but Code 2 is preferred.
E) All three are correct, but Code 3 is preferred.

Question 20

Write a program that prompts the user to enter an integer n (assume n >= 2) and displays its largest factor other than itself.

Question 21

The reverse method is defined in the textbook. What is list1 after executing the following statements? int[] list1 = {1, 2, 3, 4, 5, 6};
List1 = reverse(list1);
B) list1 is 1 2 3 4 5 6
C) list1 is 0 0 0 0 0 0
D) list1 is 6 6 6 6 6 6

Question 22

Suppose a method p has the following heading: public static int[][] p()
What return statement may be used in p()?

A) return 1;
B) return {1, 2, 3};
C) return int[]{1, 2, 3};
D) return new int[]{1, 2, 3};
E) return new int[][]{{1, 2, 3}, {2, 4, 5}};

Question 23

If you declare an array double[] list = {3.4, 2.0, 3.5, 5.5}, list[1] is ________.

A) 3.4
B) 2.0
C) 3.5
D) 5.5
E) undefined

Question 24

What is the output of the following code? double[] myList = {1, 5, 5, 5, 5, 1};
Double max = myList[0];
Int indexOfMax = 0;
For (int i = 1; i < myList.length; i++) {
If (myList[i] >= max) {
Max = myList[i];
IndexOfMax = i;
}
}
System.out.println(indexOfMax);

A) 0
B) 1
C) 2
D) 3
E) 4

Question 25

In the following code, what is the printout for list2? class Test {
Public static void main(String[] args) {
Int[] list1 = {1, 2, 3};
Int[] list2 = {1, 2, 3};
List2 = list1;
List1[0] = 0; list1[1] = 1; list2[2] = 2;
For (int i = 0; i < list2.length; i++)
System.out.print(list2[i] + " ");
}
}

A) 1 2 3
B) 1 1 1
C) 0 1 2
D) 0 1 3