#include <bits/stdc++.h>
#include "rect.h"
using namespace std;
using ll = long long;
ll n, m;
long long count_rectangles(std::vector<std::vector<signed> > a) {
n = a.size();
m = a[0].size();
vector<vector<bool> > vis(n, vector<bool>(m));
auto ok = [&](ll x, ll y) -> bool
{
return 0 <= x and x < n and 0 <= y and y < m;
};
const ll dx[] = {0, +1, 0, -1},
dy[] = {+1, 0, -1, 0};
ll x = n + 1, y = m + 1, xx = -1, yy = -1, sz = 0;
auto comp_dfs = [&] (auto&& dfs, ll i, ll j) -> void
{
assert(ok(i, j) and !vis[i][j] and a[i][j] == 0);
++sz;
vis[i][j] = true;
x = min(x, i);
xx = max(xx, i);
y = min(y, j);
yy = max(yy, j);
for(ll d = 0; d < 4; ++d) {
ll ii = i + dx[d], jj = j + dy[d];
if(!ok(ii, jj) or vis[ii][jj] or a[ii][jj] == 1) {
continue;
}
dfs(dfs, ii, jj);
}
};
ll ans = 0;
for(ll i = 0; i < n; ++i) {
for(ll j = 0; j < m; ++j) {
if(vis[i][j] or a[i][j] == 1) {
continue;
}
x = n + 1, y = m + 1, xx = -1, yy = -1, sz = 0;
comp_dfs(comp_dfs, i, j);
if(x > xx or y > yy or x <= 0 or n - 1 <= xx or y <= 0 or m - 1 <= yy) {
continue;
}
const ll ar = (xx - x + 1) * (yy - y + 1);
if(ar == sz) {
ans++;
}
}
}
return ans;
}
/*
5 5
1 1 1 1 1
1 0 0 0 1
1 1 1 1 1
1 0 1 0 1
1 1 1 1 1
*/
