While loop in c

A while loop allows a part of the code to be executed multiple times depending upon a given Boolean condition. it called a pre-tested loop. Then the ‘While loop’ is mostly used in the case where the number of repetitions is no known in advance.

Syntax of while loop:-

          While(condition)

          {

               Statement;

               Increament/decreasement;

          }

Flowchart:-

Example:-

Problem 1

Write a C program to calculate the sum of two numbers without using the plus operator.

Algorithm

Step 1   a++;  b--;

Step 2   Repeat Step 1 until b becomes 0

Program of the above problem

#include <stdio.h>

 

int main()

{

    int a, b;

    printf("a=");

    scanf("%d", &a);

    printf("b=");

    scanf("%d", &b);

 

    while (b != 0)

    {

        a++;

        b--;

    }

    printf("sum = %d\n", a);

    return 0;

}

Output:-

Note:  This logic is design for only positive integers.

Problem 2

Write a C program to the counting of the number 1 to 10 using a while loop.

#include<stdio.h>

 

int main()

{

    int i=1;

 

    while(i<=10)

    {

        printf("%d\n", i);

        i++;

    }

    return 0;

 

}

Output:-

Problem 3

Write a C program to print the 2s table using a while loop.

#include <stdio.h>

 

int main()

{

    int a, n, i;

    printf("number");

    scanf("%d", &n);

    (i = 1);

    while (i<=n)

    {

        a = 2 * i;

        {

            printf("%d\n", a);

        }

        i++;

    }

}

Output:-