Submission #1160614

#	Time	Username	Problem	Language	Result	Execution time	Memory
1160614		Nonoze	Ball Machine (BOI13_ballmachine)	C++20	60.85 / 100	143 ms	46380 KiB

ballmachine

/*
*	Author: Nonoze
*	Created: Sunday 02/03/2025
*/
#include <bits/stdc++.h>
using namespace std;

#ifndef IN_LOCAL
	#define dbg(...)
#endif

// #define cout cerr << "OUT: "
#define endl '\n'
#define endlfl '\n' << flush
#define quit(x) return (void)(cout << x << endl)

template<typename T> void read(T& x) { cin >> x;}
template<typename T1, typename T2> void read(pair<T1, T2>& p) { read(p.first), read(p.second);}
template<typename T> void read(vector<T>& v) { for (auto& x : v) read(x); }
template<typename T1, typename T2> void read(T1& x, T2& y) { read(x), read(y); }
template<typename T1, typename T2, typename T3> void read(T1& x, T2& y, T3& z) { read(x), read(y), read(z); }
template<typename T1, typename T2, typename T3, typename T4> void read(T1& x, T2& y, T3& z, T4& zz) { read(x), read(y), read(z), read(zz); }
template<typename T> void print(vector<T>& v) { for (auto& x : v) cout << x << ' '; cout << endl; }

#define sz(x) (int)(x.size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define make_unique(v) sort(all(v)), v.erase(unique(all(v)), (v).end())
#define pb push_back
#define mp(a, b) make_pair(a, b)
#define fi first
#define se second
#define cmin(a, b) a = min(a, b)
#define cmax(a, b) a = max(a, b)
#define YES cout << "YES" << endl
#define NO cout << "NO" << endl
#define QYES quit("YES")
#define QNO quit("NO")

#define int long long
#define double long double
const int inf = numeric_limits<int>::max() / 4;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD = 1e9+7, LOG=20;



void solve();

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int tt=1;
	// cin >> tt;
	while(tt--) solve();
	return 0;
}




int n, q;
vector<vector<int>> adj, up;
vector<int> val, depth;
vector<priority_queue<pair<int, int>, vector<pair<int, int>>, greater<>>> nxt;

void dfsinit(int u) {
	val[u]=u;
	for (auto v: adj[u]) {
		depth[v]=depth[u]+1;
		up[v][0]=u;
		for (int i=1; i<LOG; i++) {
			if (up[v][i-1]==-1) break;
			up[v][i]=up[up[v][i-1]][i-1];
		}
		dfsinit(v);
		cmin(val[u], val[v]);
		nxt[u].push({val[v], v});
	}
}

int lca(int u, int v) {
	if (depth[u]<depth[v]) swap(u, v);
	for (int i=LOG-1; i>=0; i--) {
		if (depth[u]-(1<<i)>=depth[v]) u=up[u][i];
	}
	if (u==v) return u;
	for (int i=LOG-1; i>=0; i--) {
		if (up[u][i]!=up[v][i]) u=up[u][i], v=up[v][i];
	}
	return up[u][0];
}

void solve() {
	read(n, q);
	adj.clear(), adj.resize(n);
	int root=0;
	for (int i=0; i<n; i++) {
		int x; read(x); x--;
		if (x==-1) root=i;
		else adj[x].pb(i);
	}
	val.clear(), val.resize(n), nxt.clear(), nxt.resize(n), up.clear(), up.resize(n, vector<int>(LOG, -1)), depth.clear(), depth.resize(n);
	dfsinit(root);
	int act=root;
	while (!adj[act].empty()) act=nxt[act].top().se;
	vector<bool> vis(n, 0);
	while (q--) {
		int type; read(type);
		if (type==1) {
			int k; read(k);
			int lst=0;
			while (k--) {
				lst=act;
				vis[act]=1;
				act=up[act][0];
				if (act==-1) break;
				nxt[act].pop();
				while (!nxt[act].empty()) act=nxt[act].top().se;
			}
			cout << lst+1 << endl;
		} else {
			int x; read(x); x--;
			int ans=0;
			for (int i=LOG-1; i>=0; i--) {
				if (up[x][i]!=-1 && vis[up[x][i]]) x=up[x][i], ans+=1<<i;
			}
			vis[x]=0;
			if (up[x][0]==-1) act=x;
			else {
				nxt[up[x][0]].push({val[x], x});
				if (lca(up[x][0], act)==up[x][0]) act=x;
			}
			cout << ans << endl;
		}
	}
}

• Subtask 1: 5.7692 / 25
• Subtask 2: 12.8571 / 30
• Subtask 3: 40 / 40
• Subtask 4: 2.2222 / 5