Submission #977471

#	Time	Username	Problem	Language	Result	Execution time	Memory
977471		Amaarsaa	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	182 ms	27960 KiB

supertrees

#include "supertrees.h"
 
#include <bits/stdc++.h>
using namespace std;
 
int cmp[1000];
bool used[1000];
vector<pair<int, int>> has[4];
vector<int> cn[1000];
 
int find(int A) {
	while (A != cmp[A]) A = cmp[A], cmp[A] = cmp[cmp[A]];
	return A;
}
 
void onion(int A, int B) { cmp[find(A)] = find(B); }
 
int construct(vector<vector<int>> p) {
	int n = p.size();
 
	for (int i = 0; i < n; i++) for (int j = 0; j < i; j++) {
		has[p[i][j]].push_back({i, j});
	}
 
	vector<vector<int>> ans(n, vector<int>(n, 0));
 
	iota(cmp, cmp + n, 0);
	for (pair<int, int> i : has[1]) onion(i.first, i.second);
	for (int i = 0; i < n; i++) cn[find(i)].push_back(i);
	for (int i = 0; i < n; i++) {
		if (!cn[i].size()) continue;
		for (int j = 1; j < cn[i].size(); j++) {
			ans[cn[i][j]][cn[i][0]] = ans[cn[i][0]][cn[i][j]] = 1;
			used[cn[i][j]] = true;
		}
		cn[i].clear();
	}
 
	for (pair<int, int> i : has[2]) onion(i.first, i.second);
	for (int i = 0; i < n; i++) if (!used[i]) cn[find(i)].push_back(i);
	for (int i = 0; i < n; i++) {
		if (cn[i].size() < 2) {
			cn[i].clear();
			continue;
		}
		if (cn[i].size() == 2) return 0;
		ans[cn[i][0]][cn[i].back()] = ans[cn[i].back()][cn[i][0]] = 1;
		for (int j = 1; j < cn[i].size(); j++)
			ans[cn[i][j]][cn[i][j - 1]] = ans[cn[i][j - 1]][cn[i][j]] = 1;
		cn[i].clear();
	}
 
	if (has[3].size()) return 0;
	for (pair<int, int> i : has[0]) if (find(i.first) == find(i.second)) return 0;
	build(ans);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:32:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |   for (int j = 1; j < cn[i].size(); j++) {
      |                   ~~^~~~~~~~~~~~~~
supertrees.cpp:48:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |   for (int j = 1; j < cn[i].size(); j++)
      |                   ~~^~~~~~~~~~~~~~

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