C – While Loop

While loop: Execute a block of instructions repeatedly until the condition is false. We use while loop only when don’t know the number of iterations to do.

Syntax:

while(condition)
{
	statements;
}

Flow Chart

Program to display digits of number in reverse order:

int main() {             int n;                printf(“Enter num : “);             scanf(“%d”, &n);             while(n!=0)             {                         printf(“%d \n”, n%10);                         n=n/10;             }             return 0; }

Program to count the digits in given number:

int main() {             int n, count=0;             printf(“Enter num : “);             scanf(“%d”, &n);             while(n!=0)             {                         n=n/10;                         count++;             }             printf(“Digits count : %d \n”, count);             return 0; }