80 pts桥条

#include <iostream>
#define ioss ios::sync_with_stdio(0);cin.tie(0);
#define ret return 
#define ll long long
#define endl cout<<'\n'
using namespace std;
ll n,S,L;
ll a[200001],h[200001],sum;
int check(ll x){
	ll tmp=0;
	for(int i=1;i<=n;i++){
		ll now=h[i]+a[i]*x;
		if(now>=L){
			tmp+=now;
		}
		if(tmp>=S) ret 1;
	}
	ret 0;
}
int main(){
	ioss
	cin>>n>>S>>L;
	for(int i=1;i<=n;i++){
		cin>>h[i];
		if(h[i]>=L) sum+=h[i];
	}
	for(int i=1;i<=n;i++) cin>>a[i];
	if(sum>=L){
		cout<<0;
		ret 0;
	}
	ll l=1,r=1e18;
	while(l<r){
		ll mid=l+r>>1;
		if(check(mid)) r=mid;
		else l=mid+1;
	}
	cout<<r;
	return 0;
}