floodfill算法系列一＞岛屿的最大面积

整体思路：

代码设计：

代码呈现：

class Solution {int ret,m,n,count;boolean[][] vis;public int maxAreaOfIsland(int[][] grid) {m = grid.length;n = grid[0].length;vis = new boolean[m][n];for(int i = 0; i < m; i++)for(int j = 0; j < n; j++){if(!vis[i][j] && grid[i][j] == 1){count = 0;dfs(grid,i,j);ret = Math.max(ret,count);}}return ret; }int[] dx = {0,0,1,-1};int[] dy = {-1,1,0,0}; private void dfs(int[][] grid, int i, int j){count++;vis[i][j] = true;//使用过就标记for(int k = 0; k < 4; k++){int x = i + dx[k]; int y = j + dy[k];if(x >= 0 && x < m && y >= 0 && y < n && !vis[x][y] && grid[x][y] == 1){dfs(grid,x,y);}}}
}