#include <bits/stdc++.h>
using namespace std;
int digitos(long long x){
    int cont = 0;
    while(x>0){
        x/=10;
        cont++;
    }
    return cont;
}

int main(){
    int n;
    long long k = 1;
    bool go = true;
    while(cin>>n){
        while(go){
            if(k%n==0){
                cout<<digitos(k)<<"\n";
                go = false;;
            }
            k = ((k*10)+1)%n;
        }
        go = true;
        k = 1;
    }

}