/BCACM11E - Phương án bắn pháo

              #include <iostream>
        #include <queue>
        using namespace std;
         
        bool* visited = new bool[101]{ false };
         
        void BFS(int arr[][101], int n, int index) {
          queue <int> iDex;
          iDex.push(index);
          visited[index] = true;
          while (!iDex.empty()) {
            int index = iDex.front();
            iDex.pop();
            for (int i = 1; i <= n; i++) {
              if (arr[index][i] == 1 && !visited[i]) {
                visited[i] = true;
                iDex.push(i);
              }
            }
          }
         
        }
         
        int get(int arr[][101], int n) {
          int num = 0;
          for (int i = 1; i <= n; i++) {
            if (!visited[i]) {
              num++;
              BFS(arr, n, i);
            }
          }
          return num;
        }
         
        void reset() {
          for (int i = 1; i <= 101; i++) {
            visited[i] = false;
          }
        }
         
        int main() {
          int t;
          cin >> t;
         
          while (t--) {
            int n;
            cin >> n;
         
            int arr[101][101];
            int brr[101][101];
         
            for (int i = 1; i <= n; i++) {
              for (int j = 1; j <= n; j++) {
                cin >> arr[i][j];
                //brr[i][j] = arr[i][j];
              }
            }
         
            int maxNumOfConnection = get(arr, n);
         
            //cout << maxNumOfConnection << endl;
         
            int iDe;
            int result = 0;
            for (int i = 1; i <= n; i++) {
              iDe = i;
              for (int i = 1; i <= n; i++) {
                for (int j = 1; j <= n; j++) {
                  if (iDe == i || iDe == j) {
                    brr[i][j] = 0;
                  }
                  else brr[i][j] = arr[i][j];
                }
              }
         
              reset();
              visited[iDe] = true;
              int numOfConnection = get(brr, n);
         
              if (numOfConnection > maxNumOfConnection) {
                maxNumOfConnection = numOfConnection;
                result = i;
              }
            }
         
            cout << result << endl;
            reset();
          }
         
          return 0;
        }