#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int n,m,j,k;
int main(){
	cin>>n>>m;
	j=n;
	k=n;
	while (j>m){
		j=j-m;
		k++;
		j=j+1;
			
	}
	cout<<k;
	return 0;
}