Even Grid

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int n;
    cin >> n;
    
    vector<vector<char>> matrix(n, vector<char>(n));
    
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cin >> matrix[i][j];
        }
    }
    
    for (int i = 1; i < n; i++) {
        for (int j = 1; j < n; j++) {
            if (matrix[i][j] == '?') {
                int row_ones = 0;
                for (int k = 0; k < j; k++) {
                    row_ones += (matrix[i][k] == '1');
                }
                for (int k = j + 1; k < n; k++) {
                    if (matrix[i][k] != '?') {
                        row_ones += (matrix[i][k] == '1');
                    }
                }
                
                int col_ones = 0;
                for (int k = 0; k < i; k++) {
                    col_ones += (matrix[k][j] == '1');
                }
                
                if ((row_ones % 2) == (col_ones % 2)) {
                    matrix[i][j] = '0';
                } else {
                    matrix[i][j] = '1';
                }
            }
        }
    }
    
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cout << matrix[i][j];
        }
        cout << endl;
    }
    
    return 0;
}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: WRONG ANSWER