credit.c

#include<cs50.h>
#include<stdio.h>

int main(void)
{
    
    long num = get_long("Number: ");
    int rez = num % 10;
    int nn = 1;
    int sum = 0; 
    while ( num > 10)
    {
       
        num /= 10;
        nn++;
        rez = num % 10;
        if (nn % 2 == 0)
        {
            
            if (rez*2 >= 10)
            {
                int f = (rez*2)/10;
                int s = (rez*2)%10;
                sum = sum + f + s;
            }
            sum = sum + rez*2;
        }
        printf("%ld %d %d % d\n", num, rez, nn, sum);
        
    }
    
    
}