Submission #1125404

#	Time	Username	Problem	Language	Result	Execution time	Memory
1125404		Agageldi	Ball Machine (BOI13_ballmachine)	C++20	0 / 100	117 ms	113180 KiB

ballmachine

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define N 4000005
#define ff first
#define ss second
#define pb push_back
#define sz(s) (int)s.size()
#define rep(c, a, b) for(c = a; c <= b; c++)

int n, t, q, m;
vector <int> v[N];
deque <int> ans;

void solve(int x) {
	vector <int> s;
	s.clear();
	for(auto i : v[x]) {
		s.pb(i);
	}
	sort(s.begin(),s.end());
	for(auto i : s) {
		solve(i);
	}
	ans.pb(x);
	return;
}

int main () {
	ios::sync_with_stdio(0);cin.tie(0);
	cin >> n >> q;
	for(int i = 1; i <= n; i++) {
		int x;
		cin >> x;
		if(x)v[x].pb(i);
		else t = i;
	}
	solve(t);
	for(int i = 1; i <= q; i++) {
		int x;
		cin >> t >> x;
		while(t != x) {
			if(sz(ans) == 0) {
				cout << "-1\n";
				return 0;
			}
			ans.pop_front();
			t++;
		}
		cout << ans[0] << '\n';
		ans.pop_front();
	}
}

• Subtask 1: 0 / 25
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40
• Subtask 4: 0 / 5