Codeforces_460A

//Codeforces Round 460A
#include <iostream>
using namespace std;
int main()
{
    int n, m, answ=0, ch=0;
    cin >> n >> m;
    while(n)
    {
        ch++;
        answ++;
        n--;
        if(ch%m==0){n++;}
    }
    cout << answ;
    return 0;
}