|
| 1 | +class Node(object): |
| 2 | + |
| 3 | + def __init__(self, elem=-1, lchild=None, rchirld=None): |
| 4 | + self.elem = elem |
| 5 | + self.lchild = lchild |
| 6 | + self.rchirld = rchirld |
| 7 | + |
| 8 | + |
| 9 | +class Tree(object): |
| 10 | + |
| 11 | + def __init__(self, root=None): |
| 12 | + self.root = root |
| 13 | + |
| 14 | + def add(self, elem): |
| 15 | + node = Node(elem) |
| 16 | + if self.root == None: |
| 17 | + self.root = node |
| 18 | + else: |
| 19 | + queue = [] |
| 20 | + queue.append(self.root) |
| 21 | + """cur = queue.pop(0) |
| 22 | + 对已有的节点进行遍历""" |
| 23 | + while queue: |
| 24 | + cur = queue.pop(0) |
| 25 | + if cur.lchild == None: |
| 26 | + cur.lchild = node |
| 27 | + return |
| 28 | + elif cur.rchirld == None: |
| 29 | + cur.rchirld = node |
| 30 | + return |
| 31 | + else: |
| 32 | + queue.append(cur.lchild) |
| 33 | + queue.append(cur.rchirld) |
| 34 | + |
| 35 | + |
| 36 | +"""Depth First Search""" |
| 37 | +def preorder(self, root): |
| 38 | + """递归实现先序遍历""" |
| 39 | + if root == None: |
| 40 | + return |
| 41 | + print root.elem |
| 42 | + self.preorder(root.lchild) |
| 43 | + self.preorder(root.rchirld) |
| 44 | + |
| 45 | +def inorder(self, root): |
| 46 | + """递归实现中序遍历""" |
| 47 | + if root == None: |
| 48 | + return |
| 49 | + self.inorder(root.lchild) |
| 50 | + print root.elem |
| 51 | + self.inorder(root.rchirld) |
| 52 | + |
| 53 | +def postorder(self, root): |
| 54 | + if root == None: |
| 55 | + return |
| 56 | + self.postorder(root.lchild) |
| 57 | + self.postorder(root.rchirld) |
| 58 | + print root.elem |
| 59 | + |
| 60 | +"""Breadth First Search""" |
| 61 | +def breadth_travel(self, root): |
| 62 | + """利用队列实现树的层次遍历""" |
| 63 | + if root == None: |
| 64 | + return |
| 65 | + queue = [] |
| 66 | + queue.append(root) |
| 67 | + while queue: |
| 68 | + node = queue.pop(0) |
| 69 | + print node.elem |
| 70 | + if node.lchild != None: |
| 71 | + queue.append(node.lchild) |
| 72 | + if node.rchirld != None: |
| 73 | + queue.append(node.rchirld) |
| 74 | + |
| 75 | + |
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