#include <iostream>
using namespace std;
int main(){
    int a,b;cin>>a>>b;
    for(int i = 1; 1000 >= i; i++){
        
        for(int j = 0; i >= j; j++){
            int A = (j*1000)/i,B = ((i-j)*1000)/i;
            if(A%10 < 5)A/=10;
            else A=A/10+1;
            if(B%10 < 5)B/=10;
            else B=B/10+1;
            if(max(A,B) == max(a,b) && min(A,B) == min(a,b)){
                cout << i << endl;
                return 0;
            }
            
        }
    }
}