Commit 5bf1117

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hj.tian

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feat: add leetcode75 day34

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	`1`	`+from collections import defaultdict`
	`2`	`+from typing import List`
	`3`	`+`
	`4`	`+`
	`5`	`+class Solution:`
	`6`	`+ def findCircleNum(self, isConnected: List[List[int]]) -> int:`
	`7`	`+ """`
	`8`	`+ 1. 构建有向图 edges:`
	`9`	`+ {`
	`10`	`+ 0: [1],`
	`11`	`+ 1: [0],`
	`12`	`+ 2: [],`
	`13`	`+ }`
	`14`	`+ 2. 广度优先搜索次数即为省份数量`
	`15`	`+ """`
	`16`	`+ n = len(isConnected)`
	`17`	`+ if n < 1 or len(isConnected[0]) < 1:`
	`18`	`+ raise KeyError`
	`19`	`+ edges = defaultdict(list)`
	`20`	`+ for i in range(n):`
	`21`	`+ for j in range(n):`
	`22`	`+ if i != j and isConnected[i][j] == 1:`
	`23`	`+ edges[i].append(j)`
	`24`	`+ visit = [False for _ in range(n)]`
	`25`	`+ ans = 0`
	`26`	`+ for i in range(n):`
	`27`	`+ if visit[i] is False:`
	`28`	`+ self.bfs(edges, i, visit)`
	`29`	`+ ans += 1`
	`30`	`+ return ans`
	`31`	`+`
	`32`	`+ def bfs(self, edges, start, visit):`
	`33`	`+ queue = [start]`
	`34`	`+ while queue:`
	`35`	`+ size = len(queue)`
	`36`	`+ for i in range(size):`
	`37`	`+ visit[queue[i]] = True`
	`38`	`+ for city in edges[queue[i]]:`
	`39`	`+ if visit[city] is False:`
	`40`	`+ queue.append(city)`
	`41`	`+ queue = queue[size:]`
	`42`	`+`
	`43`	`+`
	`44`	`+if __name__ == "__main__":`
	`45`	`+ assert Solution().findCircleNum(isConnected=[[1, 1, 0], [1, 1, 0], [0, 0, 1]]) == 2`
	`46`	`+ assert Solution().findCircleNum(isConnected=[[1, 0, 0], [0, 1, 0], [0, 0, 1]]) == 3`

Lines changed: 42 additions & 0 deletions

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	`1`	`+from collections import defaultdict`
	`2`	`+from typing import List`
	`3`	`+`
	`4`	`+`
	`5`	`+class Solution:`
	`6`	`+ def removeStones(self, stones: List[List[int]]) -> int:`
	`7`	`+`
	`8`	`+ n = len(stones)`
	`9`	`+ if n < 1:`
	`10`	`+ raise KeyError`
	`11`	`+ edges = defaultdict(list)`
	`12`	`+ for i in range(n):`
	`13`	`+ for j in range(i + 1, n):`
	`14`	`+ if stones[i][0] == stones[j][0] or stones[i][1] == stones[j][1]:`
	`15`	`+ edges[i].append(j)`
	`16`	`+ # notes, 是双向图`
	`17`	`+ edges[j].append(i)`
	`18`	`+ visit = [False for _ in range(n)]`
	`19`	`+ connected = 0`
	`20`	`+ for i in range(n):`
	`21`	`+ if visit[i] is False:`
	`22`	`+ self.bfs(edges, i, visit)`
	`23`	`+ connected += 1`
	`24`	`+ return n - connected`
	`25`	`+`
	`26`	`+ def bfs(self, edges, start, visit):`
	`27`	`+ queue = [start]`
	`28`	`+ while queue:`
	`29`	`+ size = len(queue)`
	`30`	`+ for i in range(size):`
	`31`	`+ visit[queue[i]] = True`
	`32`	`+ for city in edges[queue[i]]:`
	`33`	`+ if visit[city] is False:`
	`34`	`+ queue.append(city)`
	`35`	`+ queue = queue[size:]`
	`36`	`+`
	`37`	`+`
	`38`	`+if __name__ == "__main__":`
	`39`	`+ assert Solution().removeStones(stones=[[0, 0], [0, 1], [1, 0], [1, 2], [2, 1], [2, 2]]) == 5`
	`40`	`+ assert Solution().removeStones(stones=[[0, 0], [0, 2], [1, 1], [2, 0], [2, 2]]) == 3`
	`41`	`+ assert Solution().removeStones(stones=[[0, 0]]) == 0`
	`42`	`+ assert Solution().removeStones(stones=[[0, 1], [1, 0], [1, 1]]) == 2`

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