Study of nested while loop.

#include <stdio.h>

int main(void)
{
int i, j;

i = 1;

while(i <= 3) /* outer loop */
{
j = 1;

while(j <= 5) /* nested (inner) loop */
{
printf("\n%d\t%d", i, j);
j++;
}

i++;
}

return 0;
}