Submission

Score: 100

User: Kitsunox

Problemset: Red Zone

Language: cpp

Time: 0.053 second

Submitted On: 2025-12-22 08:23:08

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

bool check(int md){
    vector<int> mp(n+5,0);
    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;
    }
    int damage = 0;
    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,r = m + 1;
    while(lo < r){
        int md = (lo+r)/2;
        if(check(md)) r = md;
        else lo = md + 1;
    }
    if(lo == m+1)cout << "-1";
    else cout << lo;
}