While Loop

What is the main purpose of a 'While' loop in programming?

• To repeat a set of instructions a specific number of times

• To repeat a set of instructions as long as a condition is true

• To declare variables

• To print text on the screen

If the condition in a 'While' loop is initially false, how many times will the loop execute?

• 1 time

• 0 times

• Infinite times

• Depends on the code inside the loop

Answer explanation

The condition for 'While' loop is checked at the start. If at the very start of the loop, the condition evaluates to False, then the code inside the loop will not be executed at all.

In VB, what keyword is used to mark the end of a 'While' loop?

• End While

• Next

• End Loop

• Loop Until

What will be the output of the following VB code if X is set to 1 (X = 1) before the start of the 'While' loop?

• Hello

• Hello

  Hello

• Hello

  Hello

  Hello

• Infinite Loop

Answer explanation

X is initially 1. (X = 1)

As long as the condition X <= 3 in the While loop is true, the word "Hello" will be printed on screen.

X is incremented by 1 (X = X + 1) to prevent infinite loop.

So, "Hello" will be printed 3 times (when X = 1, X = 2 and X = 3).

Identify the error in this VB code.

• The 'While' keyword is incorrect

• The condition i >= 1 is incorrect

• The loop does not update the value of variable i, causing an infinite loop

• The loop will not execute at all

Answer explanation

The value of i is initially 10.

The While keyword is correctly written.

The condition of the While loop is true (since i >= 1).

The loop will be executed and the value of i will be printed on screen.

But notice that the the value of i is not decremented before the 'While' loop ends.

This causes i to remain at value 10 each time the loop executes, causing infinite loop.