#include <bits/stdc++.h>   using namespace std;   int main() {     int x, y, i = 1, s, p, q;     cin >> x >> y;     s = x % 10;     q = s;     p = s;     while (p % 10 != 0 || p != y) {       if (p % 10 == 0 || p == y) {         break;       }       i++;       q = q + s;       p = q % 10;     }     cout << i;   }   