Submission #389729

#	Time	Username	Problem	Language	Result	Execution time	Memory
389729		SuhaibSawalha1	Split the Attractions (IOI19_split)	C++17	40 / 100	124 ms	14428 KiB

split

#include "split.h"
#include <bits/stdc++.h>
using namespace std;
 
vector<vector<int>> adj;
vector<bool> vis;
int n, m;
vector<int> ord, k, ans;
 
void dfs (int u) {
	vis[u] = 1;
	for (int v : adj[u]) {
		if (!vis[v]) {
			dfs(v);
		}
	}
	ord.push_back(u);
}
 
void go (int i) {
	while (k[i]) {
		--k[i];
		ans[ord.back()] = i + 1;
		ord.pop_back();
	}
}

void color (int u, int p, int c) {
	if (k[c] && !ans[u]) {
		ans[u] = c + 1;
		--k[c];
	}
	else {
		return;
	}
	for (int v : adj[u]) {
		if (v ^ p) {
			color(v, u, c);
		}
	}
}

int dfs2 (int u, int p = -1) {
	int s = 1;
	for (int v : adj[u]) {
		if (v ^ p) {
			s += dfs2(v, u);
		}
	}
	for (int i = 0; i < 3; ++i) {
		if (k[i] && s >= k[i]) {
			color(u, p, i);
			return 0;
		}
	}
	return s;
}
 
vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
	::n = n;
	k = {a, b, c};
	m = p.size();
	adj.resize(n);
	ans.resize(n);
	vis.resize(n);
	for (int i = 0; i < m; ++i) {
		adj[p[i]].push_back(q[i]);
		adj[q[i]].push_back(p[i]);
	}
	array<int, 2> P[n];
	for (int i = 0; i < n; ++i) {
		P[i] = {(int)adj[i].size(), i};
	}
	sort(P, P + n);
	if (m == n - 1) {
		dfs2(P[n - 1][1]);
		if (count(k.begin(), k.end(), 0) < 2) {
			return vector<int>(n, 0);
		}
		for (int i = 0; i < n; ++i) {
			if (!ans[i]) {
				ord.push_back(i);
			}
		}
	}
	else {
		dfs(P[0][1]);
	}
	for (int i = 0; i < 3; ++i) {
		go(i);
	}
	return ans;
}

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36