#include <stdio.h>
main()
{
    int d = 0;
    int n;

    printf("Enter a nonnegative integer: ");
    scanf("%d", &n);

    do
    {
        n = n / 10;
        d = d + 1;
    }
    while (n > 0);

    printf("Result: %d \n", d);

    return 0;
}