Submission #1125590

#	Time	Username	Problem	Language	Result	Execution time	Memory
1125590		Agageldi	Ball Machine (BOI13_ballmachine)	C++20	12.38 / 100	369 ms	126516 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 = 1, vis[N], par[N], r, dis[N], sp[N][30], vip[N];
vector <int> v[N];
set <int> ans, jog;

void solve(int x) {
	vector <pair<int,int>> s;
	for(auto i : v[x]) s.pb({dis[i],i});
	sort(s.begin(),s.end());
	for(auto i:s) solve(i.ss);
	vis[m] = x;
	ans.insert(m);
	m++;
}
void dfs(int x) {
	for(auto i:v[x]) {
		dfs(i);
		dis[x] = min(dis[x],dis[i]);
	}
	dis[x] = min(x,dis[x]);
}

int main () {
	ios::sync_with_stdio(0);cin.tie(0);
	cin >> n >> q;
	for(int i = 0; i <= n; i++) {
		dis[i] = INT_MAX;
	}
	for(int i = 1; i <= n; i++) {
		int x;
		cin >> x;
		par[i] = x;
		sp[i][0] = x;
		if(x) v[x].pb(i);
		else r = i;
	}
	for(int i = 1; i <= 20; i++) {
		for(int j = 1; j <= n; j++) {
			if(sp[j][i - 1]) sp[j][i] = sp[sp[j][i - 1]][i - 1];
		}
	}
	dfs(r);
	solve(r);
	for(int i = 1; i <= q; i++) {
		int x;
		cin >> t >> x;
		if(t == 1) {
			for(int j = 1; j <= x; j++) {
				jog.insert(*ans.begin());
				ans.erase(*ans.begin());
			}
			cout << vis[*(--jog.end())] << '\n';
			continue;
		}
		int jg = x, cnt = 0;
		for(int j = 20; j >= 0; j--) {
			if(jog.find(sp[jg][j]) != jog.end()) {
				jg = sp[jg][j];
				cnt += (1 << j);
			}
		}
		cout << cnt << '\n';
		ans.insert(*jog.begin());
		jog.erase(*jog.begin());
	}
}

• Subtask 1: 0 / 25
• Subtask 2: 10.7143 / 30
• Subtask 3: 0 / 40
• Subtask 4: 1.6667 / 5