JAVA for loops and while loops

What is the correct function of a for loop?

• To check for conditions after executing the statements

• To be a control flow statement that allows code to be executed repeatedly based on a given Boolean condition.

• To determine a boolean variable as true or false.

• To consume the initialization, condition and increment/decrement in one line thereby providing a shorter, easy to debug structure of looping.

What is an Increment/ Decrement?

• It initializes the variable in use.

• It is used for updating the variable for next iteration.

• It marks the start of a for loop.

• It is used for testing the exit condition for a loop.

What is the output of the following code segment?

class forLoopDemo

{ public static void main(String args[])

{ // for loop begins when x=2

// and runs till x <=4

for (int x = 2; x <= 4; x++)

System.out.println("Value of x:" + x);

}

}

• Value of x:2

  Value of x:3

  Value of x:4

• Value of x:1

  Value of x:2

  Value of x:3

• Value of x:2

  Value of x:2

  Value of x:4

• Value of x:2

  Value of x:3

  Value of x:3

What is the correct function of a while loop?

• A control flow statement that allows code to be executed repeatedly based on a given Boolean condition.

• To consume the initialization, condition and increment/decrement in one line

• To initialize the variable in use.

• To check for condition after executing the statements

What is the correct output for the following code segment?

class whileLoopDemo

{

public static void main(String args[])

{

int x = 1;

// Exit when x becomes greater than 4

while (x <= 4)

{

System.out.println("Value of x:" + x);

// Increment the value of x for

// next iteration

x++;

}

}

}

• Value of x:1

  Value of x:2

  Value of x:4

• Value of x:1

  Value of x:2

  Value of x:3

• Value of x:1

  Value of x:2

  Value of x:3

  Value of x:4

• Value of x:2

  Value of x:2

  Value of x:3

  Value of x:4

What are 3 general types of loops in Java?

• for loops, while loops and do loops

• while loops, do loops and hit loops

• kin loops, for loops and multi loops

• for loops, while loops and multi loops

What must the test be so that the following fragment prints out the integers 5 through and including 15?

for ( int j = 5; ________ ; j++ )

{

System.out.print( j + " " );

}

System.out.println( );

• j<15

• j<=16

• j<16

• j==15

What is the output of the following program fragment?

for ( int j = 0; j < 5; j++ )

{

System.out.print( j + " " );

}

System.out.println( );

• 0 1 2 3 4 5

• 0 1 2 3 4

• 0 1 2 3 4 5

• j j j j j

What must change so the following fragment prints out the even integers 0 2 4 6 8 10?

for ( int j = 0; j <= 10; _______ )

{

System.out.print( j + " " )

}

System.out.println( );

• j+2

• j = j+2

• j++++

• ++j++

What is the output of the following code fragment?

for ( int j = 5; j > -5; j-- )

{

System.out.print( j + " " );

}

System.out.println( );

• -5 -4 -3 -2 -1 0

• 5 4 3 2 1 0

• 5 4 3 2 1 0 -1 -2 -3 -4 -5

• 5 4 3 2 1 0 -1 -2 -3 -4