#include<bits/stdc++.h>
//#include "supertrees.h"
using namespace std;
vector < int > adj[1002];
int ataman[10002], used[1002];
int Get(int x) {
if ( x == ataman[x]) return x;
return ataman[x] = Get(ataman[x]);
}
void Unite(int x, int y) {
x = Get(x);
y = Get(y);
if (x == y) return ;
if ( x < y) swap(x, y);
ataman[x]= y;
}
int construct(vector<vector<int>> a) {
int n = a.size(), i, j;
vector < vector < int > > ans(n, vector<int>(n, 0));
for (i = 0; i < n; i ++) ataman[i]= i;
int s = 1;
for ( i = 0; i < n; i++) {
for ( j = 0; j < n; j ++) {
if ( a[i][j] == 1 && i != j) Unite(i, j);
}
}
for (i = 0; i < n; i ++) {
for (j = 0; j < n; j ++) {
if ( i == j) continue;
if ( (a[i][j] == 0 || a[i][j] == 3) && Get(i) == Get(j)) s= 0;
if ( a[i][j] == 1 && Get(i) != Get(j)) s = 0;
}
}
for (i = 0; i < n; i ++) {
vector < int > v;
v.push_back(i);
for (j = i + 1; j < n; j ++) {
if ( Get(j) == Get(i) && !used[j]) v.push_back(j);
}
used[i] = 1;
for (j = 1; j < v.size(); j ++) {
used[v[j]] = 1;
ans[v[j]][v[j - 1]] = ans[v[j - 1]][v[j]] = 1;
}
}
for (i = 0; i < n; i ++) ataman[i] = i;
for (i = 0; i < n; i ++) {
for (j = 0; j < n; j ++) {
if ( a[i][j] == 2 && i != j) Unite(i, j);
}
}
for (i = 0; i < n; i ++) used[i] = 0;
for (i = 0; i < n; i ++) {
for (j = 0; j < n; j ++) {
if ( i == j) continue;
if ( (a[i][j] == 0 || a[i][j] == 3) && Get(i) == Get(j)) s= 0;
if ( a[i][j] == 2 && Get(i) != Get(j)) s = 0;
}
}
for (i = 0; i < n; i ++) {
vector < int > v;
v.push_back(i);
for (j = i + 1; j < n; j ++) {
if ( Get(j) == Get(i) && !used[j]) v.push_back(j);
}
if(v.size() == 1) continue;
if ( v.size() == 2){
s = 0;
break;
}
used[i] = 1;
for (j = 1; j < v.size(); j ++) {
used[v[j]] = 1;
ans[v[j]][v[j - 1]] = ans[v[j - 1]][v[j]] = 1;
}
ans[v[0]][v[v.size() -1]] = ans[v[v.size() -1]][v[0]] = 1;
}
if ( s == 0) return 0;
build(ans);
return s;
}
/*
vector < vector < int > > b;
inp() {
int n, i, j, x;
cin >>n;
b.resize(n);
for (i = 0; i < n; i ++) {
for (j = 0; j < n; j ++) {
cin >> x;
b[i].push_back(x);
}
}
}
int main() {
inp();
cout << construct(b) << endl;
}
*/
Compilation message
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:42:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
42 | for (j = 1; j < v.size(); j ++) {
| ~~^~~~~~~~~~
supertrees.cpp:75:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
75 | for (j = 1; j < v.size(); j ++) {
| ~~^~~~~~~~~~
supertrees.cpp:83:2: error: 'build' was not declared in this scope
83 | build(ans);
| ^~~~~