Submission #1010197

#	Time	Username	Problem	Language	Result	Execution time	Memory
1010197		nickolasarapidis	Closing Time (IOI23_closing)	C++17	0 / 100	392 ms	403324 KiB

closing

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

#define ll long long

const int MAXN = 200000;

vector<pair<int, int> > adj[MAXN];

vector<ll> disX(MAXN);
vector<ll> disY(MAXN);

int ans = 0;
int ans2 = 0;

void dfsPrecompute(int s, int e, int X){
	for(auto u : adj[s]){
		if(u.first != e){
			if(X == 0){
				disX[u.first] = disX[s] + u.second;
				dfsPrecompute(u.first, s, X);
			}
			else{
				disY[u.first] = disY[s] + u.second;
				dfsPrecompute(u.first, s, X);
			}
		}
	}
}

void dfs(int s, int e, vector<ll> C, int X){
	ans++;
	for(auto u : adj[s]){
		if(X == 0){
			if(u.first != e and disX[u.first] <= C[u.first]){
				dfs(u.first, s, C, X);
			}
		}
		else{
			if(u.first != e and disY[u.first] <= C[u.first]){
				dfs(u.first, s, C, X);
			}
		}
	}
}

int max_score(int N, int X, int Y, ll K, vector<int> U, vector<int> V, vector<int> W){
	ans = 0; ans2 = 0;
	
	disX.clear();
	disY.clear();
	
	for(int i = 0; i < N; i++){
		adj[i].clear();
	}
	
	for(int i = 0; i < N - 1; i++){
		adj[U[i]].push_back({V[i], W[i]});
		adj[V[i]].push_back({U[i], W[i]});
	}

	vector<tuple<ll, ll, int> > dis(N);

	vector<ll> C(N, 0);
	vector<ll> C2(N, 0);

	disX[X] = 0;
	disY[Y] = 0;

	ll sum = 0;

	dfsPrecompute(X, -1, 0);
	dfsPrecompute(Y, -1, 1);

	for(int i = 0; i < N; i++){
		get<0>(dis[i]) = min(disX[i], disY[i]);
		get<1>(dis[i]) = max(disX[i], disY[i]);
		get<2>(dis[i]) = i;
	}

	sort(dis.begin(), dis.begin() + N - 1);

	for(int i = 0; i < N; i++){
		if(get<2>(dis[i]) != X and get<2>(dis[i]) != Y){
			if(sum + get<0>(dis[i]) <= K){
				if(sum + get<1>(dis[i]) <= K){
					C[get<2>(dis[i])] = get<1>(dis[i]);
					sum += C[get<2>(dis[i])];
				}
				else{
					C[get<2>(dis[i])] = get<0>(dis[i]);
					sum += C[get<2>(dis[i])];
				}
			}
			else{
				break;
			}
		}
	}

	dfs(X, -1, C, 0);
	dfs(Y, -1, C, 1);
	
	ans2 = ans;
	ans = 0;
	
	for(int i = 0; i < N; i++){
		if(sum + get<0>(dis[i]) <= K){
			if(sum + get<1>(dis[i]) <= K){
				C2[get<2>(dis[i])] = get<1>(dis[i]);
				sum += C2[get<2>(dis[i])];
			}
			else{
				C2[get<2>(dis[i])] = get<0>(dis[i]);
				sum += C2[get<2>(dis[i])];
			}
		}
		else{
			break;
		}
	}
	
	dfs(X, -1, C2, 0);
	dfs(Y, -1, C2, 1);

	return max(ans, ans2);
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 12
• Subtask 4: 0 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17