func_code_string: #include <bits/stdc++.h>   using namespace std;   char mat[55][55];   int n;   int A[] = {-1, 0, 1, 0};   int B[] = {0, 1, 0, -1};   vector<pair<int, int> > ilha1, ilha2;   void flood_fill(int i, int j, bool prima) {     if (i < 0 or j < 0 or i >= n or j >= n or mat[i][j] !=  0 ) return;     mat[i][j] =  1 ;     if (prima)       ilha1.push_back({i, j});     else       ilha2.push_back({i, j});     for (int k = 0; k < 4; k++) {       flood_fill(i + A[k], j + B[k], prima);     }   }   int main() {     pair<int, int> p1, p2;     scanf( %d , &n);     scanf( %d%d%d%d , &p1.first, &p1.second, &p2.first, &p2.second);     p1.first--;     p1.second--;     p2.first--;     p2.second--;     for (int i = 0; i < n; i++) {       for (int j = 0; j < n; j++) {         scanf(  %c , &mat[i][j]);       }     }     flood_fill(p1.first, p1.second, true);     if (mat[p2.first][p2.second] ==  1 ) {       puts( 0 );       return 0;     }     flood_fill(p2.first, p2.second, false);     int ans = INT_MAX;     for (int i = 0; i < (int)ilha1.size(); i++) {       for (int j = 0; j < (int)ilha2.size(); j++) {         int a = abs(ilha1[i].first - ilha2[j].first);         int b = abs(ilha1[i].second - ilha2[j].second);         ans = min(ans, a * a + b * b);       }     }     cout << ans << endl;     return 0;   }   