Submission #1291685

#	Time	Username	Problem	Language	Result	Execution time	Memory
1291685		gustavo_d	Connecting Supertrees (IOI20_supertrees)	C++20	0 / 100	1 ms	348 KiB

supertrees

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

#define sz(v) (int)(v).size()

const int MAXN = 5000;

vector<int> adj[MAXN];
vector<pair<int, int>> eds;
bool vis[MAXN];
vector<int> cycle;

void dfs(int v) {
	vis[v] = true;
	cycle.push_back(v);
	for (int viz : adj[v]) {
		if (vis[viz]) continue;
		dfs(viz);
	}
}

int construct(vector<vector<int>> paths) {
	int n = sz(paths);

	for (int i=0; i<n; i++) {
		for (int j=0; j<n; j++) {
			if (i == j) continue;
			if (paths[i][j] == 0) continue;
			adj[i].push_back(j);
		}
	}

	for (int i=0; i<n; i++) {
		if (vis[i]) continue;
		cycle.clear();
		dfs(i);

		if (sz(cycle) == 1) continue;

		for (int u : cycle) {
			for (int v : cycle) {
				if (u == v) continue;
				if (paths[u][v] == 0) return 0;
			}
		}

		for (int j=1; j<sz(cycle); j++) eds.emplace_back(cycle[j], cycle[j-1]);
		eds.emplace_back(cycle[0], cycle.back());
	}

	vector<vector<int>> ans(n, vector<int> (n, 0));
	// cerr << sz(eds) << '\n';
	for (auto [u, v] : eds) {
		// cerr << u << ' ' << v << '\n';
		ans[u][v] = ans[v][u] = 1;
	}
	build(ans);
	return 1;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4