#include<bits/stdc++.h>
using namespace std;
#define int long long
int32_t main(){
   int n,k; cin>>n>>k;
   int l = 1ll,r = 1e10,ans;
   while(l<=r)
   {
       int md = l + (r - l)/2;
       int v = (md + k - 1ll)/k;
       if(v * v >= n)
       ans = md,r = md - 1ll;
       else l = md+1ll;
   }
   cout<<ans;


   return 0;
   }