Submission #381900

#	Time	Username	Problem	Language	Result	Execution time	Memory
381900		pavement	Connecting Supertrees (IOI20_supertrees)	C++17	0 / 100	2 ms	364 KiB

supertrees

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

int link[1005], sz[1005];
vector<int> vec[1005];

int find(int x) {
	if (x == link[x]) return x;
	return link[x] = find(link[x]);
}

void unite(int a, int b) {
	a = find(a);
	b = find(b);
	if (a == b) return;
	if (sz[b] > sz[a]) swap(a, b);
	sz[a] += sz[b];
	for (int i : vec[b]) vec[a].push_back(i);
	link[b] = a;
}

int construct(vector<vector<int> > p) {
	int n = p.size();
	for (int i = 0; i < n; i++) {
		link[i] = i;
		sz[i] = 1;
		vec[i].push_back(i);
	}
	vector<vector<int> > b(n, vector<int>(n));
	for (int i = 0; i < n; i++)
		for (int j = i + 1; j < n; j++)
			if (p[i][j]) unite(i, j);
	for (int i = 0; i < n; i++) {
		if (find(i) != i) continue;
		int prv = -1;
		for (int j : vec[i]) {
			if (prv != -1) b[prv][j] = b[j][prv] = 1;
			prv = j;
		}
		if (vec[i][0] != vec[i].back()) {
			b[vec[i][0]][vec[i].back()] = 1;
			b[vec[i].back()][vec[i][0]] = 1;
		}
	}
	bool inv = 0;
	for (int i = 0; i < n; i++)
		for (int j = 0; j < n; j++)
			if (find(i) == find(j) && !p[i][j]) inv = 1;
			else if (find(i) != find(j) && p[i][j]) inv = 1;
	if (inv) return 0;
	build(b);
	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