This is very similar to the while loop except that the test occurs at the end of the loop body. This guarantees that the loop is executed at least once before continuing. The test then verifies the data, and loops back to read again if it was unacceptable

The do while Loop

This is very similar to the while loop except that the test occurs at the end of the loop body. This guarantees that the loop is executed at least once before continuing.

Such a setup is frequently used where data is to be read. The test then verifies the data, and loops back to read again if it was unacceptable.

do
{
printf("Enter 1 for yes, 0 for no :");
scanf("%d", &input_value);

} while (input_value != 1 && input_value != 0)

To better understand the do while loop let us see the following example:

#include <stdio.h>

int main()
{
int i;

i = 0;
do
{
printf("The value of i is now %d\n", i);
i = i + 1;
} while (i < 5);

return 0;
}

The result of the program is displayed as follows:

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