@@ -170,6 +170,81 @@ public:
170170
171171# 其它语言版本
172172
173+ ## Python
174+ ### BFS
175+ ```python
176+ class Solution:
177+ def __init__(self):
178+ self.count = 0
179+
180+ def maxAreaOfIsland(self, grid: List[List[int]]) -> int:
181+ # 与200.独立岛屿不同的是:此题grid列表内是int!!!
182+
183+ # BFS
184+ if not grid: return 0
185+
186+ m, n = len(grid), len(grid[0])
187+ visited = [[False for i in range(n)] for j in range(m)]
188+
189+ result = 0
190+ for i in range(m):
191+ for j in range(n):
192+ if not visited[i][j] and grid[i][j] == 1:
193+ # 每一个新岛屿
194+ self.count = 0
195+ print(f'{self.count}')
196+ self.bfs(grid, visited, i, j)
197+ result = max(result, self.count)
198+
199+ return result
200+
201+ def bfs(self, grid, visited, i, j):
202+ self.count += 1
203+ visited[i][j] = True
204+
205+ queue = collections.deque([(i, j)])
206+ while queue:
207+ x, y = queue.popleft()
208+ for new_x, new_y in [(x + 1, y), (x - 1, y), (x, y - 1), (x, y + 1)]:
209+ if 0 <= new_x < len(grid) and 0 <= new_y < len(grid[0]) and not visited[new_x][new_y] and grid[new_x][new_y] == 1:
210+ visited[new_x][new_y] = True
211+ self.count += 1
212+ queue.append((new_x, new_y))
213+ ```
214+ ### DFS
215+ ``` python
216+ class Solution :
217+ def __init__ (self
218+ self .count = 0
219+ 220+ def maxAreaOfIsland (self grid : List[List[int ]]) -> int :
221+ # DFS
222+ if not grid: return 0
223+ 224+ m, n = len (grid), len (grid[0 ])
225+ visited = [[False for _ in range (n)] for _ in range (m)]
226+ 227+ result = 0
228+ for i in range (m):
229+ for j in range (n):
230+ if not visited[i][j] and grid[i][j] == 1 :
231+ self .count = 0
232+ self .dfs(grid, visited, i, j)
233+ result = max (result, self .count)
234+ return result
235+ 236+ def dfs (self grid , visited , x , y ):
237+ if visited[x][y] or grid[x][y] == 0 :
238+ return
239+ visited[x][y] = True
240+ self .count += 1
241+ for new_x, new_y in [(x + 1 , y), (x - 1 , y), (x, y + 1 ), (x, y - 1 )]:
242+ if 0 <= new_x < len (grid) and 0 <= new_y < len (grid[0 ]):
243+ self .dfs(grid, visited, new_x, new_y)
244+ ```
245+ 246+ 247+ 173248## Java
174249
175250这里使用深度优先搜索 DFS 来完成本道题目。我们使用 DFS 计算一个岛屿的面积,同时维护计算过的最大的岛屿面积。同时,为了避免对岛屿重复计算,我们在 DFS 的时候对岛屿进行 "淹没" 操作,即将岛屿所占的地方置为 0。
@@ -199,4 +274,4 @@ public int dfs(int[][] grid,int i,int j){
199274 dfs(grid,i,j + 1 ) +
200275 dfs(grid,i,j - 1 );
201276}
202- ```
277+ ```
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