1000 digits

[carlious]

I'm currently doing this problem:
http://coj.uci.cu/24h/problem.xhtml?pid=1102
which is actually a very easy problem, just that I have a slight problem, how do I store 1000 digit integers? Here is my current code, although the online judge keeps saying wrong answer because my code can't store 1000 digit integers.

#include <stdio.h>
#include <iostream>
using namespace std;

int main() {
    unsigned long x, r;
    for (;;) {
        scanf("%lu", &x);
        r=x%11;
        if (x==0) {
            break;
        }
        if (r==0){
            printf("%lu", x); printf("%s\n", " is a multiple of 11.");
        }
        else{
            printf("%lu", x); printf("%s\n", " is not a multiple of 11.");
        }
    }
}

[shadowmouse]

Either use a bignum library if you can find no other way of doing it (seems like a bad idea) or store the characters in a string and use a more advanced algorithm to determine if it is a multiple of eleven.

[carlious]

How would I do any of those 2 options? I'm fairly new to coding.

[MiiNiPaa]

https://www.math.hmc.edu/funfacts/ffiles/10013.5.shtml
Just read number in a string, then iterate over string applying divisibility by 11 algorithm.

[carlious]

And how do I do that? I'm sorry for being so stubborn, I just really don't know how to do this.

[MiiNiPaa]

#include <iostream>
#include <string>

int main()
{
    std::string number;
    std::cin >> number;
    int result = 0;
    for(int i = 0; i < number.size(); ++i) {
        int digit = number[i] - '0';
        //Do calculations with current digit
    }
    //Use result to determine if it is divisible by 11;
}

[carlious]

Thanks!!