#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
int p[2000], mark[2020];
int find (int u) { return u==p[u]? u:p[u]=find(p[u]); }
bool merge (int i, int j) {
// cerr << "merge " << find(i) << ' ' << find(j) << endl;
if (find(i) == find(j)) return false;
p[find(i)] = find(j);
return true;
}
void log (vector<vector<int>> s) {
cerr << "log" << endl;
for (auto x : s) {
for (auto y : x) {
cerr << y << ' ';
} cerr << endl;
}
cerr << endl;
}
int construct(vector<vector<int>> req) {
// cerr << "hi" << endl;
int n = req.size();
vector<vector<int>> answer;
for (int i = 0; i < n; i++) {
vector<int> row;
row.resize(n);
answer.push_back(row);
}
iota(p, p+n+1, 0);
bool flag = true;
for (int i = 0; i < n; i++) {
for (int j = i+1; j < n; j++) {
if (req[i][j] == 1) {
// assert(merge(i, j));
if (merge(i, j)) {
answer[i][j] = answer[j][i] = 1;
}
}
}
}
for (int i = 0; i < n; i++) {
for (int j = i+1; j < n; j++) {
// cerr << i << ' ' << j << ' ' << find(i) << ' ' << find(j) << endl;
if (req[i][j] == 0 and find(i) == find(j)) flag = false;
}
}
if (flag == false) return 0;
build(answer);
return 1;
}
