#include "rect.h"
#ifndef EVAL
#include "grader.cpp"
#endif
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2505;
int n, m, dp[N][N];
vector<vector<int>> a;
inline bool check(int r1, int c1, int r2, int c2){
for(int i=r1;i<=r2;i++){
for(int j=c1;j<=c2;j++){
int t = min(min(a[i][c1-1], a[i][c2+1]), min(a[r1-1][j], a[r2+1][j]));
if(a[i][j] >= t)return false;
}
}return true;
}
int get(int x1,int y1,int x2,int y2){
int res = dp[x2][y2];
if(x1&&y1)res += dp[x1-1][y1-1];
if(x1)res -= dp[x1-1][y2];
if(y1)res -= dp[x2][y1-1];
return res;
}
ll count_rectangles(vector<vector<int>> a){
::a = a;
n = a.size();
m = a[0].size();
ll ans = 0;
if(n*m <= 1){
for(int i=1;i<n-1;i++){
for(int j=1;j<m-1;j++){
for(int I=i;I<n-1;I++){
for(int J=j;J<m-1;J++){
ans += check(i,j,I,J);
}
}
}
}return ans;
}
for(int i=0;i<n;i++){
for(int j=0;j<m;j++){
dp[i][j] = a[i][j];
if(j)dp[i][j] += dp[i][j-1];
}for(int j=0;j<m;j++){
if(i)dp[i][j] += dp[i-1][j];
}
}
for(int i=1;i<n-1;i++){
for(int j=1;j<m-1;j++){
int x = i, y = j;
while(x+1 < n && a[x+1][j]==0)x++;
while(y+1 < m && a[i][y+1]==0)y++;
if(get(i,j,x,y) == 0 && get(i-1,j,i-1,y) == y-j+1 && get(x+1,j,x+1,y) == y-j+1 && get(i,j-1,x,j-1) == x-i+1 && get(i,y+1,x,y+1) == x-i+1)ans++;
}
}
return ans;
}
