#include<bits/stdc++.h>
using namespace std;
#define el "\n"
#define ll long long
#define ull unsigned long long
#define se second
#define fi first
#define be begin()
#define en end()
#define Faster cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);
int main()
{
Faster;
int n, r; cin >> n >> r;
int i = 1;
while(i)
{
if(n * i % 10 == 0 || n * i % 10 - r == 0)
{
cout << i;
return 0;
}
i++;
}
return 0;
}
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