Difference Between While Loop and Do While Loop (With Table)

While Loop vs Do While Loop

Repeated proclamations permit the arrangement of guidelines to execute consistently till the condition doesn’t turn out false. The Iteration proclamations in C++ and Java are, for circle, while circle and do while circle. These details are normally called loops.

Loops in programming come into utilization when we have to more than once execute a square of explanations. For instance: Suppose we need to print “Hello World” multiple times. This should be possible in two different ways as demonstrated as follows:

An iterative method to do this is to write the printf() statement 10 times.

// C program to illustrate need of loops
#include <stdio.h>

intmain()
{     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);     
printf( “Hello World\n”);            

return0;
}

Output:

Hello World

Hello World

Hello World

Hello World

Hello World

Hello World

Hello World

Hello World

Hello World

Hello World

The difference between while loop and do while loop is that while loop check condition before emphasis of the loop. Then again, the do-while loop checks the condition after the execution of the details inside the loop.Another difference that is to be noted down arethat the while loop is known as the section-controlled loop and the do while loop is otherwise known as the exit-controlled loop.


 

Comparison Table Between While Loop and Do While Loop (in Tabular Form)

Parameters of the comparisonWhile loopDo while loop
What is it?When an if statement is repeated multiple times, based on a Boolena condition, then it is called a while loop. Unlike while or of loop, the condition here is checked only at the bottom of the loop. The execution of the statement takes places at least once.
VariablesYou can find the variables being booted at the beginning of executing the loop.The variables are initialized either within the loop or before the loop begins.
Brackets and semicolonsIf we have just one statement, then there is nil need of brackets. No semicolons at the end of the while. No matter the no. of statements present in the program, brackets are always required. Similarly, semicolons should be there at the end of the do while loop.
Type of loopIt is an entry-controlled loop. It is an exit-controlled loop.
Basic formatwhile (condition) {statements; }do { statements } while (expression);

 

What is While Loop?

The while loop is the most fundamental loop available in C++ and Java. The working of a while loop is similar in both C++ and Java.

The while loop first verifies the condition, and if the condition is true, then, it iterates the loop till the condition turns out false. The condition in while loop can be any Boolean expression.

When an expression returns any non-zero value, then the condition is “true”, and if the expression returns a zero value, the condition becomes “false”. If the condition becomes true, then loop iterates itself, and if the condition becomes false, then the control passes to the next line of the code immediately followed by the loop.

The statements or the body of the loop can either be an empty statement or a single statement or a block of statements.

While Loop
 

What is Do While Loop?

As in the while loop, in the event that the controlling condition turns out to be false in the main emphasis just, at that point the body of the while circle isn’t executed in any way.

In any case, the do-while circle is fairly not the same as while loop. The do-while loop executes the body of the circle at any rate once regardless of whether the condition is false at the principal endeavor.

In a do-while circle, the collection of loop happens before the controlling condition and the contingent expression is at the base of the loop. As in while loop, the body can be unfilled as both C++ and Java permit invalid explanations or, there can be just can be a statement or a set of statements. The condition here is additionally a Boolean articulation, which is valid for all non-zero merit. In a do-while loop, the control first reaches to the detail in the body of a do-while loop. The details in the body get executed first, and afterward the control arrives at the condition part of the loop. The condition is confirmed and, if it is accurate, the loop is iterated once more, and in the event that the condition is bogus, at that point the control resumes to the following line following the loop.

Do While Loop 1

Main Differences Between While Loop and Do While Loop

  • The while loop checks the condition at the beginning of the loop and if the condition is well explained inside the loop, is executed. Whereas in the do-while loop, the condition is checked after the execution of all statements in the body of the loop.
  • By chance if the condition in some time loop is false, not a solitary explanation inside the loop is executed. Conversely, in the event that the condition in do-while loop is counterfeit, at that point additionally the body of the loop is executed at any rate once then the condition is examined.
  • The while loop is otherwise called the passage controlled and pre-checking loop on the grounds that in this loop, the body of the loop is executed before checking the condition. Then again, the alternate name for the do-while loop is the exit-controlled and post-checking loop, the explanation for this is the checking of the loop condition is trailed by the execution of the body of the loop.
  • The language structure of a do-while loop incorporates a semi-colon to end the loop. Actually, there is no utilization of the semi-colon in the while loop punctuation.
  • In while loop, initially the condition is checked and then comes the execution of the statement. But in do while loop, only after the statement is executed at least once then after that the condition is checked.

 

Conclusion

You may experience circumstances, when a block of code should be executed a few number of times. As a rule, explanations are executed successively: The principal statement in a capacity is executed first, trailed constantly, etc. Programming dialects give different control structures that are considered more entangled execution ways. A loop articulation permits us to execute an announcement or gathering of proclamations on different occasions.

 

Word Cloud for Difference Between While Loop and Do While Loop

The following is a collection of the most used terms in this article on While Loop and Do While Loop. This should help in recalling related terms as used in this article at a later stage for you.

Difference Between While Loop and Do While Loop