rt，感觉A<C<B<F<<D<E<G

E题3个点死活过不了

#include<bits/stdc++.h>
using namespace std;
int N;long double H[202412],X[202412];
bool chk(long double h){
	long double maxsight=-1./0.;
	for(int i=1;i<=N;i++){
		if(-h+H[i]<=maxsight*X[i])return 1;
		maxsight=max(maxsight,(-h+H[i])/(X[i]));
	}return 0;
}
int main(){
	cin>>N;for(int i=1;i<=N;i++)cin>>X[i]>>H[i];
	if(!chk(0))return puts("-1"),0;
	long double L=0,R=1e19,mid=5e18;
	while((R-L)/(L+1e-9)>=1e-10){
		mid=(R+L)/2;
		if(chk(mid))L=mid;
		else R=mid;
	}printf("%.15Lf",mid);
	return 0;
}