number_of_digits_without_using_loop_v2.c

/*

    number_of_digits_without_using_loop_v2.c

    Version with recursion from Bishal Raj Bhattarai
    https://web.facebook.com/profile.php?id=100009001371943


    You can find all my C programs at Dragan Milicev's pastebin:

    https://pastebin.com/u/dmilicev

*/

#include <stdio.h>

int count_digits(long long x)
{
    static int counter=0;   // must be static because of recursion

    if( x > 0 )
    {
        count_digits(x/10);
        counter++;
    }

    return counter;
}

int main(void)
{
    long long num = 999999991234567890;
    int count;

    count = count_digits(num);

    printf("\n In number %lld there are total digits %d \n", num, count);

    printf("\n In number %llu there are total digits %d \n", num, count);


    return 0;

} // main()