Submission

Score: 100

User: Kitsunox

Problemset: Red Zone

Language: cpp

Time: 0.046 second

Submitted On: 2025-12-22 17:44:34

#include <bits/stdc++.h>
using namespace std;
const int nx = 1e5+5;
int n,m,l,d;
int ho[nx],bo[nx];

bool check(int md){
    vector<int>mp (n+5,0);
    int damage = 0;
    for(int i = 1;i <= md;i++){
        int ll = max(1,bo[i]-l);
        int rr = min(n+1,bo[i]+l+1);
        mp[ll] += d;
        mp[rr] -= d;
    }
    for(int i = 1;i <= n;i++){
        damage += mp[i];
        if(ho[i] - damage > 0)return 0;
    }
    return 1;
}

int main(){
    cin >> n >> m >> l >> d;
    for(int i = 1;i <=n;i++)cin >> ho[i];
    for(int i = 1;i <=m;i++)cin >> bo[i];
    int lo = 1,hi = m+1;
    while(lo < hi){
        int md = (lo+hi)/2;
        if(check(md)) hi = md;
        else lo = md+1;
    }
    if(lo == m+1)cout <<"-1";
    else cout << lo;
    
}