Submission #1242091

#	Time	Username	Problem	Language	Result	Execution time	Memory
1242091		trimkus	Connecting Supertrees (IOI20_supertrees)	C++20	100 / 100	124 ms	22208 KiB

supertrees

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


int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	std::vector<std::vector<int>> answer;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < n; ++j) {
			if (p[i][j] == 3) return 0;
		}
	}
	for (int i = 0; i < n; i++) {
		std::vector<int> row;
		row.resize(n);
		answer.push_back(row);
	}
	vector<bool> vis(n);
	vector<int> lidx(n), cidx(n);
	for (int it = 0; it < n; ++it) {
		if (vis[it]) continue;
		queue<int> comp;
		vector<int> cycle;
		comp.push(it);
		while (comp.size()) {
			int x = comp.front();
			comp.pop();
			if (vis[x]) continue;
			vector<int> curr_line;
			cycle.push_back(x);
			queue<int> qline;
			qline.push(x);
			while (qline.size()) {
				int y = qline.front();
				qline.pop();
				if (vis[y]) continue;
				vis[y] = 1;
				curr_line.push_back(y);
				cidx[y] = it;
				lidx[y] = x;
				for (int j = 0; j < n; ++j) {
					if (p[y][j] == 2) {
						comp.push(j);
					} else if (p[y][j] == 1) {
						qline.push(j);
					}
				}
			}
			if (curr_line.size() > 1) {
				int a = curr_line[0];
				for (int i = 1; i < (int)curr_line.size(); ++i) {
					int b = curr_line[i];
					answer[a][b] = answer[b][a] = 1;
				}
			}	
		}
		if (cycle.size() == 2) return 0;
		if (cycle.size() == 1) continue;
		for (int i = 0; i < (int)cycle.size(); ++i) {
			int a = cycle[i];
			int b = cycle[(i + 1) % cycle.size()];
			answer[a][b] = answer[b][a] = 1;
		}
	}
	for (int i = 0; i < n; ++i) {
		for (int j = i + 1; j < n; ++j) {
			if (lidx[i] == lidx[j]) {
				if (p[i][j] != 1) return 0;
			} else if (cidx[i] == cidx[j]) {
				if (p[i][j] != 2) return 0;
			} else {
				if (p[i][j] != 0) return 0;
			}
		}
	}
	build(answer);
	return 1;
}

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