Grid

#include <bits/stdc++.h>

#define ll long long
#define lll __int128
#define pii pair<int, int>
#define M 1000000007
#define N (1001)
using namespace std;

char t[N][N];
int rows[N], cols[N];

int main () {
	int n; cin >> n;
	for(int i=0; i<n; ++i) rows[i] = cols[i] = 1;
	
	for(int i=0; i<n; ++i){
		for(int j=0; j<n; ++j){
			cin >> t[i][j];
			if(t[i][j]=='0') cols[j] = rows[i] = 0;
		}
	}
	int V = 0;
	for(int i=0; i<n; ++i) if(rows[i]) ++V;
	if(V < n) {
		for(int i=0; i<n; ++i) if(cols[i]) ++V;
	}
	
	for(int i=0; i<n; ++i){
		for(int j=0; j<n; ++j) {
			if(t[i][j] == '1' && rows[i]+cols[j] == 0) V=-1;
		}
	}
	cout << V;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED