Use of mathematical operations and implementation (C language )

Problem-Finding the sum of digits of five digit number.

 #include <stdio.h>

#include <string.h>

#include <math.h>

#include <stdlib.h>

int main()

{

    int n;

    scanf("%d", &n);

    // Complete the code to calculate the sum of the five digits on n.

    int num;

    int base = 10000;

    int sum = 0;

    // printf("%d\n",(num-(num%base))/base );

    // printf("%d\n",(num%base));

    for (int i = 1; i <= 5; i++)

    {

        num = (n - (n % base)) / base;

        n = (n % base);

        base /= 10;

        sum += num;

    }

    printf("%d\n", sum);

    return 0;

}