class Solution {
public:
    bool not_valid (vector<vector<char>>& board, int i , int j)
    {
        return i < 0 || i >= board.size() || j < 0 || j >= board[0].size();
    }
    void dfs (vector<vector<char>>& board, int i , int j)
    {
        if (not_valid ( board,i, j ) || board [i][j] == '.')
            return;
        board [i][j] = '.';

        dfs (board,i + 1 , j);
        dfs (board,i - 1 , j);
        dfs (board,i, j + 1);
        dfs (board,i , j - 1);


    }
    int countBattleships(vector<vector<char>>& board) {

        int res = 0;

        for (int i = 0 ; i < board.size(); i++)
        {
            for (int j = 0 ;  j < board[0].size(); j++)
            {
                if (board[i][j] == 'X')
                {
                    res++;
                    dfs (board,i, j);
                }
            }
        }

        return res;
    }
};



only look for the first one

int countBattleships(vector<vector<char>>& board) {

        int res = 0 ;
        int szi = board.size();
        int szj = board[0].size();

        for ( int i = 0 ; i < szi ; i++)
        {
            for (int j = 0 ; j < szj ; j ++)
            {
                if (board[i][j]=='X')
                {
                    if ( (i == 0 || board[i-1][j]=='.') && (j==0 || board[i][j-1]=='.'))
                        res++;
                }

            }
        }
        return res;

    }