#include<iostream>
using namespace std;
const int N = 1e8;
int dp[N];
int ans = 0;
int cnt = 0;
int main(){
    int n, m;
    cin >> n >> m;
    dp[0] = 1;
    for(int i = 0; i < N && cnt < min(n, m); i++){
        if(dp[i]){
            cnt++;
            dp[i + n] = 1;
            dp[i + m] = 1;
        }
        else{
            ans = i;
            cnt = 0;
        }
    }
    cout << ans;
    return 0;
}