#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
template<class T, class U>
void ckmin(T &a, U b)
{
if (a > b) a = b;
}
template<class T, class U>
void ckmax(T &a, U b)
{
if (a < b) a = b;
}
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int) (x).size())
const int MAXN = 1013;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
int N;
int grid[MAXN][MAXN];
int dsu[MAXN], cc[MAXN], cc1[MAXN];
vi heads[MAXN];
vector<vi> ans;
int get(int u)
{
return (u == dsu[u] ? u : dsu[u] = get(dsu[u]));
}
bool merge(int u, int v)
{
u = get(u);
v = get(v);
if (u == v) return false;
dsu[u] = v;
return true;
}
void addedge(int i, int j)
{
if (i == j) return;
ans[i][j] = 1;
ans[j][i] = 1;
}
int construct(vector<vi> p)
{
N = SZ(p);
FOR(i, 0, N)
{
FOR(j, 0, N)
{
grid[i][j] = p[i][j];
if (grid[i][j] == 3)
{
return 0;
}
}
}
ans.resize(N);
FOR(i, 0, N)
{
ans[i].resize(N);
}
iota(dsu, dsu + N, 0);
FOR(i, 0, N)
{
FOR(j, 0, N)
{
if (grid[i][j] != 0)
{
merge(i, j);
}
}
}
FOR(i, 0, N)
{
cc[i] = get(i);
}
FOR(i, 0, N)
{
FOR(j, 0, N)
{
if (cc[i] == cc[j] && grid[i][j] == 0)
{
return 0;
}
}
}
iota(dsu, dsu + N, 0);
FOR(i, 0, N)
{
FOR(j, 0, N)
{
if (grid[i][j] == 1)
{
merge(i, j);
}
}
}
FOR(i, 0, N)
{
cc1[i] = get(i);
}
FOR(i, 0, N)
{
FOR(j, 0, N)
{
if (cc1[i] == cc1[j] && grid[i][j] != 1)
{
return 0;
}
}
addedge(i, cc1[i]);
}
FOR(i, 0, N)
{
if (cc1[i] == i)
{
heads[cc[i]].PB(i);
}
}
FOR(i, 0, N)
{
if (cc[i] == i)
{
if (SZ(heads[i]) == 2)
{
return 0;
}
FOR(j, 0, SZ(heads[i]) - 1)
{
addedge(heads[i][j], heads[i][j + 1]);
}
addedge(heads[i][0], heads[i].back());
}
}
build(ans);
//first connect all the stuff that are 1's. if you get any 0's in between then bad.
return 1;
}
