While and Do...While Loops

This video tutorial covers the basics of loops in JavaScript, focusing on while and do while loops. It explains how to implement counting loops, both forward and backward, and how to filter even numbers. The tutorial also demonstrates using while loops with string inputs and highlights the differences between while and do while loops, emphasizing when each should be used.

What is the primary purpose of a loop in programming?

• To declare variables

• To stop the execution of a program

• To repeat a block of code while a condition is true

• To execute a block of code once

In a while loop, when does the loop stop executing?

• When the condition is true

• When the condition is false

• When the user inputs a specific value

• After a fixed number of iterations

What is a common mistake when setting the continuation condition in a while loop?

• Setting the condition to stop one iteration early

• Using a complex condition

• Setting the condition to always be true

• Using a variable that is not initialized

How can you decrement a variable in a loop?

• Using the increment operator

• Using the decrement operator

• By multiplying the variable

• By dividing the variable

What does the expression 'X % 2 == 0' check for in a loop?

• If X is odd

• If X is even

• If X is greater than 2

• If X is less than 2

Which method is more flexible for outputting even numbers in a loop?

• Decrementing by 2

• Checking if the number is even

• Using a fixed array of even numbers

• Incrementing by 2

What is a key difference between a while loop and a do-while loop?

• A do-while loop checks the condition before executing

• A while loop is used for infinite loops

• A while loop always executes at least once

• A do-while loop always executes at least once

In a do-while loop, where is the condition checked?

• It is not checked

• In the middle of the loop

• At the end of the loop

• At the beginning of the loop

What happens if the initial condition in a do-while loop is false?

• The loop executes once

• The loop does not execute

• The loop throws an error

• The loop executes indefinitely

When should you use a do-while loop over a while loop?

• When you want the loop to execute at least once

• When you want the loop to never execute

• When you want to check the condition first

• When you want to use a for loop instead