/*          made by   
                                                        NAYEEM HOSSAIN           */
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;

#define loop(n) for(int i=0; i<n; i++)
#define loop_1(n,i) for(i=0; i<n; i++)
#define yes cout << "YES" << endl ;
#define no  cout << "NO" << endl ;
#define faster {ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);}
#define bi(n) bitset<8> (n) 


int main(){
    faster;
    int n,m;
    cin>>n>>m;
    int i=1;
    while(n>0){
        if(i%m==0)n++;
        n--;
        i++;
    }
    cout<<i-1<<endl;
    return 0;
}