LeetCode: Battleships in a Board

Battleships之间并不重叠这个assumption很关键，因此只要看船头就可以判断是不是有一个船

public class Solution {
    public int countBattleships(char[][] board) {
        int ans = 0;
        for (int i = 0; i < board.length; i++) {
            for (int j = 0; j < board[0].length; j++) {
                if (board[i][j] == 'X' && ((i != 0 && board[i-1][j] != 'X') || i == 0) && ((j != 0 && board[i][j-1] !='X') || j == 0))
                    ans++;
            }
        }
        return ans;
    }
}