#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll n,k,M,D,anss;
ll calc(ll x){
ll tmp=(n/x-
1)/k+
1;
return tmp;
}
int main(){
cin>>n>>k>>M>>
D;
for(ll i=
1;i<=D;i++
){
ll l=
1,r=M,mid,ans=
0;
while(l<=
r){
mid=l+r>>
1;
ll t=
calc(mid);
if(t>=i) ans=mid,l=mid+
1;
else r=mid-
1;
}
if(ans!=
0)
anss=max(anss,ans*
i);
}
cout<<anss<<
endl;
}
转载于:https://www.cnblogs.com/zsben991126/p/10668168.html
