#include "rect.h"
#include <bits/stdc++.h>
using namespace std;
#pragma GCC target("avx2,popcnt,sse4")
#pragma GCC optimize("O3,unroll-loops")
#define ll long long
vector<vector<int>> pref,arr,row,col;
int N,M;
int sum(int sr,int er,int sc,int ec){
sr++,er++,sc++,ec++;
return pref[er][ec]-pref[sr-1][ec]-pref[er][sc-1]+pref[sr-1][sc-1];
}
long long count_rectangles(std::vector<std::vector<int> > a) {
N = a.size(),M = a[0].size();
pref = vector<vector<int>>(N+1,vector<int>(M+1,0));
row = col = pref;
arr = a;
for(int i = 0;i<N;i++){
for(int j = 0;j<M;j++){
pref[i+1][j+1] = arr[i][j];
}
}
for(int i = 1;i<=N;i++){
for(int j = 1;j<=M;j++){
pref[i][j] += pref[i-1][j]+pref[i][j-1]-pref[i-1][j-1];
}
}
ll ans = 0;
for(int i = 0;i<N;i++){
for(int j = 0;j<M;j++){
if(arr[i][j]){
row[i][j] = col[i][j] = 0;
continue;
}
if(i)col[i][j] = col[i-1][j]+1;
else col[i][j] = 1;
if(j)row[i][j] = row[i][j-1]+1;
else row[i][j] = 1;
}
}
/*
cerr<<"ROW: "<<endl;
for(int i = 0;i<N;i++){
for(int j = 0;j<M;j++)cerr<<row[i][j]<<' ';cerr<<endl;
}cerr<<endl;
cerr<<"COL: "<<endl;
for(int i = 0;i<N;i++){
for(int j = 0;j<M;j++)cerr<<col[i][j]<<' ';cerr<<endl;
}cerr<<endl;
*/
for(int i = 1;i+1<N;i++){
for(int j = 1;j+1<M;j++){
if(!row[i][j])continue;
int h = col[i][j],w = row[i][j];
if(i<h||j<w)continue;
if(sum(i-h+1,i,j-w+1,j) == 0){
cerr<<"ZERO: "<<i<<' '<<j<<":"<<h<<' '<<w<<endl;
}
if(sum(i-h+1,i,j+1,j+1) == sum(i-h+1,i,j-w,j-w) && sum(i-h+1,i,j+1,j+1) == h&&
sum(i-h,i-h,j-w+1,j) == sum(i+1,i+1,j-w+1,j)&&sum(i-h,i-h,j-w+1,j) == w&&
sum(i-h+1,i,j-w+1,j) == 0)ans++;
}
}
return ans;
}
