What is the Difference Between while and do while loop?

The main difference between a while loop and a do-while loop is the way they check the condition for executing the loop. Here are the key differences between while and do-while loops:

1. Execution: A while loop checks the condition before executing the loop. If the condition is false, the loop statements are executed zero times. On the other hand, a do-while loop checks the condition after executing the loop. The loop body is executed at least once, even if the condition is false.
2. Control Flow: A while loop is an entry-controlled loop, meaning the condition is checked before entering the loop. If the condition is false, the loop is not executed. A do-while loop is an exit-controlled loop, meaning the condition is checked after the loop has been executed.
3. Condition Initialization: In a while loop, the counter variable is initialized before the loop, and the loop continues as long as the condition holds true. In a do-while loop, the counter variable can be initialized before and after the loop, allowing for multiple initializations.

In summary, you should use a while loop when you want to execute a block of code zero or more times, depending on a condition. A do-while loop should be used when you want to execute a block of code at least once, and then continue executing it zero or more times, depending on a condition.

Comparative Table: while vs do while loop

The main differences between while and do-while loops are:

In summary, a while loop checks the condition before executing the statement(s) and may execute the statement(s) zero times if the condition is false. In contrast, a do-while loop executes the statement(s) at least once and then checks the condition, which may lead to the statement(s) being executed only once if the condition is false.