https://www.luogu.com.cn/problem/P5788

#include<bits/stdc++.h>
using namespace std;
const int N = 10000010;
typedef long long LL;
typedef list<int>::iterator Iter;
list<int> L;
deque<int> dq;
queue<int> q;
stack<int> s;
// int a[N], ans[N];
int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin >> n;
    vector<int> a(n + 1, 0), ans(n + 1, 0);
    for (int i = 1; i <= n; i ++ ) cin >> a[i];
    for (int i = n; i >= 1; i -- ) {
        while (!s.empty() && a[s.top()] <= a[i]) s.pop();
        if (s.empty()) ans[i] = 0;
        else ans[i] = s.top();
        s.push(i);
    }
    for (int i = 1; i <= n; i ++ ) cout << ans[i] << " ";
    return 0;
}