#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long

ll n,s,l;
ll hs[1145141];
ll as[1145141];

bool check(int m){
	ull sum=0,x;
	for(int i=0;i<n;i++){
		x=hs[i]+as[i]*m;
		if(x>=l) sum+=x;
		else continue;
	}
	if(sum>=s) return 1;
	else return 0;
}

int main(){
	cin>>n>>s>>l;
	for(int i=0;i<n;i++){
		cin>>hs[i];
	}
	for(int i=0;i<n;i++){
		cin>>as[i];
	}
	
	ll low=0,r=1e18,mid;
	while(low<=r){
		mid=(low+r)>>1;
		if(check(mid)) r=mid-1;
		else low=mid+1;
	}
	cout<<low;
}