並查集 Python實現

標籤：iss   node   ==   code   直接   stack   sel   fat   AC   

 1 # 並查集實現 2 class Node: 3     pass 4  5 class UnionFindSet: 6     def __init__(self, nodes): 7         self.fatherDict = dict() 8         self.sizeDict = dict() 9         for node in nodes:10             self.fatherDict[node] = node11             self.sizeDict[node] = 112 13     # def findHead(self, node):14     #     father = self.fatherDict.get(node)15     #     if node!=father:16     #         father = self.findHead(father)17     #     self.fatherDict[node] = father18     #     return father19 20     def findHead(self, node):           # 找到當前節點的頭21         stack = []                      # 每次查詢都會最佳化，經過的節點會直接指向頭結點22         father = self.fatherDict[node]23         while node != father:24             stack.append(node)25             node = father26             father = self.fatherDict[node]27         while len(stack) > 0:28             self.fatherDict[stack.pop()] = father29         return father30 31     def isSameSet(self, a, b):32         return self.findHead(a) == self.findHead(b)33 34     def uion(self, a, b):                  # 兩集合合并35         if a is None or b is None:36             return37         aHead = self.findHead(a)38         bHead = self.findHead(b)39         if aHead != bHead:40             aSize = self.sizeDict[aHead]41             bSize = self.sizeDict[bHead]42             if aSize <= bSize:43                 self.fatherDict[aHead] = bHead44                 self.sizeDict[bHead] = aSize + bSize45             else:46                 self.fatherDict[bHead] = aHead47                 self.sizeDict[aHead] = aSize + bSize

 

並查集 Python實現