class Solution {
public:
int countBattleships(vector<vector<char>>& board) {
int m = board.size();
int n = board[0].size();
int res = 0;
for (int i=0; i<m; i++) {
for (int j =0; j<n; j++) {
if ((board[i][j]=='X')&&(i==0||board[i-1][j]!='X')&&(j==0||board[i][j-1]!='X')) {
++res;
}
}
}
return res;
}
};
