C :

#include<stdio.h>

int main()
{
    int a,b,t,sum;
    while(~scanf("%d%d",&a,&b))
    {
        sum=0;
        t=0;
        while(a&&b)
        {
            if((a%10+b%10+t)>9)
            {
                sum++;
                t=1;
            }
            else
            t=0;
            a=a/10;
            b=b/10;
        }
        printf("%d\n",sum);
    }
    return 0;
}

C++ :

#include <stdio.h>

int main()

{
    int a,b;
    int cnt ;
    while(~scanf("%d%d",&a,&b))
    {
        cnt = 0;
        int r ;
        int f = 0;
        while(a)
        {
            r = a % 10 + b % 10 + f;
            if(r > 9){
                cnt++;
                f = 1;
            }
            else f = 0;
            a /= 10;
            b /= 10;
        }
        printf("%d\n",cnt);
    }
    return 0;
}