标签：ret 层次遍历 elf app span pytho print back 深度
python实现二叉树的数据结构：
. 二叉树的排序方式：
- 广度遍历（层次遍历）
- 深度遍历：
- 前序（根左右）：把根放到最前面
- 中序（左根右）：把根放到中间
- 后序（左右根）：把根放到最后
class Node(): def __init__(self,item): self.item = item self.right = None self.left = None class Tree(): def __init__(self): self.root = None def add(self,item): node = Node(item) if self.root is None: self.root = node return else: queue = [self.root] while queue: cur = queue.pop(0) if cur.left is None: cur.left = node return else: queue.append(cur.left) if cur.right is None: cur.right = node return else: queue.append(cur.right) #广度遍历 def travel(self): if self.root is None: print(‘‘) return else: queue = [self.root] while queue: cur = queue.pop(0) print(cur.item) if cur.left is not None: queue.append(cur.left) if cur.right is not None: queue.append(cur.right) #深度遍历：前序，中序，后序遍历 def forwordTravel(self,root): if root is None: return print(root.item,end=‘ ‘) self.forwordTravel(root.left) self.forwordTravel(root.right) def middleTravel(self,root): if root is None: return self.middleTravel(root.left) print(root.item,end=‘ ‘) self.middleTravel(root.right) def backTravel(self,root): if root is None: return self.backTravel(root.left) self.backTravel(root.right) print(root.item,end=‘ ‘) tree = Tree() tree.add(‘0‘) tree.add(‘1‘) tree.add(‘2‘) tree.add(‘3‘) tree.add(‘4‘) tree.add(‘5‘) tree.add(‘6‘) tree.add(‘7‘) tree.add(‘8‘) tree.add(‘9‘) tree.travel() tree.forwordTravel(tree.root) print(‘\n‘) tree.backTravel(tree.root) print(‘\n‘) tree.middleTravel(tree.root) print(‘\n‘)
python实现排序二叉树：
#排序二叉树 class Node(): def __init__(self,item): self.item = item self.left = None self.right = None class Tree(): def __init__(self): self.root = None def insert(self,item): node = Node(item) cur = self.root if cur is None: self.root = node return while True: if item < cur.item: if cur.left is None: cur.left = node return else: cur = cur.left else: if cur.right is None: cur.right = node return else: cur = cur.right def preTravel(self,root): if root is None: return print(root.item,end=‘ ‘) self.preTravel(root.left) self.preTravel(root.right) def middleTravel(self,root): if root is None: return self.middleTravel(root.left) print(root.item,end=‘ ‘) self.middleTravel(root.right) def backTravel(self,root): if root is None: return self.backTravel(root.left) self.backTravel(root.right) print(root.item,end=‘ ‘) tree = Tree() tree.insert(3) tree.insert(8) tree.insert(5) tree.insert(7) tree.insert(6) tree.preTravel(tree.root) print(‘\n‘) tree.middleTravel(tree.root) print(‘\n‘) tree.backTravel(tree.root) print(‘\n‘)
标签：ret 层次遍历 elf app span pytho print back 深度
原文地址：https://www.cnblogs.com/bobo-zhang/p/10856009.html
