#include<bits/stdc++.h>
#define N 100001 
#define ll long long
using namespace std;
ll n , a[N] , m , p , s1 , s2 , ls , hs; 
int main(){
    cin >> n;
    for(int i = 1;i <= n;i++)cin >> a[i];
    cin >> m >> p >> s1 >> s2;
    a[p] += s1;
    for(int i = 1;i < m;i++){
    	ls += (m - i) * a[i];
	}
	for(int i = m + 1;i <= n;i++){
		hs += (i - m) * a[i];
	}
	if(hs > ls){
		if((hs - ls) % s2 == 0&&((hs - ls) / s2) < m)cout <<  m -(hs - ls) / s2;
		else cout << m - (hs - ls) / s2;
	}else if(ls>hs){
		cout << m + (ls - hs) / s2;
	}else{
		cout << m;
	}
	return 0;
}

蒟蒻的代码