Programación Competitiva

#include <bits/stdc++.h>
using namespace std;

int main() {
    int num;
    while(scanf("%d",&num)==1){
        int ones = 0, c =-1;
        while(c!=0){
            if(c==-1) c=0;
            c = (c*10+1)%num;
            ones++;
        }
        printf("%d\n",ones);
    }
    return 0;
}