題目

https://leetcode.com/problems/battleships-in-a-board/

題解

一道簡單的 medium 題，仍然是“感染”的思想，只不過本題“感染”的過程是消除的過程。

class Solution {int M;int N;int count;public int countBattleships(char[][] board) {M = board.length;N = board[0].length;count = 0;for (int i = 0; i < M; i++) {for (int j = 0; j < N; j++) {if (board[i][j] == 'X') {count++;bfsErase(board, i, j);}}}return count;}public void bfsErase(char[][] board, int i, int j) {if (i < 0 || j < 0 || i >= M || j >= N) return;board[i][j] = '.';if (i > 0 && board[i - 1][j] == 'X') {bfsErase(board, i, j);} else if (j > 0 && board[i][j - 1] == 'X') {bfsErase(board, i, j - 1);} else if (i < M - 1 && board[i + 1][j] == 'X') {bfsErase(board, i + 1, j);} else if (j < N - 1 && board[i][j + 1] == 'X') {bfsErase(board, i, j + 1);}} }

總結(jié)

以上是生活随笔為你收集整理的leetcode 419. Battleships in a Board | 419. 甲板上的战舰（二维矩阵DFS经典“感染”思路）的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

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