func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1005;   int n, m, b[N][N], a[N][N];   void solve() {     if (n % 2) {       printf( %d n , n);       return;     }     bool ok = 1;     while (n > 1 && ok && n % 2 == 0) {       for (int i = 0; i < n; i++) {         for (int j = 0; j < m; j++) {           if (b[i][j] != b[n - i - 1][j]) {             ok = 0;             break;           }         }       }       if (ok) n /= 2;     }     printf( %d n , n);   }   int main() {     ios::sync_with_stdio(false);     scanf( %d %d , &n, &m);     for (int i = 0; i < n; i++)       for (int j = 0; j < m; j++) scanf( %d , &b[i][j]);     solve();     return 0;   }   