2019-07-08

Author: JiayangWu

0133.克隆图/0133-克隆图.py

@@ -0,0 +1,64 @@
+"""
+# Definition for a Node.
+class Node(object):
+    def __init__(self, val, neighbors):
+        self.val = val
+        self.neighbors = neighbors
+"""
+class Solution(object):
+    def cloneGraph(self, node):
+        """
+        :type node: Node
+        :rtype: Node
+        """
+        from collections import defaultdict, deque
+        record = defaultdict(list)
+        mapping = dict()
+        def bfs(queue):
+            if not queue:
+                return
+            newqueue = deque()
+            
+            while queue:
+                cur = queue.popleft()
+                mapping[cur] = Node(cur.val, [])
+                for nei in cur.neighbors:
+                    record[cur].append(nei)
+                    if nei not in visited:
+                        visited.add(nei)
+                        newqueue.append(nei)
+            bfs(newqueue)
+         
+        visited = {node}           
+        q = deque()
+        q.append(node)
+        bfs(q)
+        
+        # for key, val in record.items():
+        #     print key.val
+        #     for item in val:
+        #         print item.val
+        # print mapping
+        visited = {node}
+        
+        def generate(queue):
+            while queue:
+                newqueue = []
+                for node in queue:
+                    if node:
+                        # print node.val                    
+                        if not record[node]: #如果没有邻居
+                            return
+
+                        for nei in record[node]: #处理每个邻居
+                            mapping[node].neighbors.append(mapping[nei])
+                            if nei not in visited:
+                                visited.add(nei)
+                                newqueue.append(nei)
+                queue = newqueue[:]
+        q = deque()
+        q.append(node)
+        generate(q)
+
+        return mapping[node]
+