[何海涛] 求二元查找树的镜像

题目:输入一颗二元查找树,将该树转换为它的镜像,即在转换后的二元查找树中,左子树的结点都大于右子树的结点。用递归和循环两种方法完成树的镜像转换。

例如输入:

     8
    /  \
  6      10
 /\       /\
5  7    9   11

输出:

      8
    /  \
  10    6
 /\      /\
11  9  7  5

 

递归或者栈模拟

 1 #include <iostream>
 2 #include <stack>
 3 using namespace std;
 4 
 5 struct Node
 6 {
 7     int val;
 8     Node *left;
 9     Node *right;
10     Node():left(NULL), right(NULL){}
11 };
12 
13 void convert(Node *root)
14 {
15     if (root == NULL)
16         return;
17 
18     convert(root->left);
19     convert(root->right);
20     Node *node = root->left;
21     root->left = root->right;
22     root->right = node;
23 }
24 
25 void stackConvert(Node *root)
26 {
27     stack<Node* > s;
28     s.push(root);
29 
30     while(!s.empty())
31     {
32         Node *node = s.top();
33         s.pop();
34 
35         Node *temp = node->left;
36         node->left = node->right;
37         node->right = temp;
38 
39         if (node->left)
40             s.push(node->left);
41         if (node->right)
42             s.push(node->right);
43     }
44 }
45 
46 void print(Node *node)
47 {
48     if (node == NULL)
49         return;
50 
51     cout << "Node:" << node << " val:" << node->val << " left:" << node->left << " right:" << node->right << endl;
52 
53     print(node->left);
54     print(node->right);
55 }
56 
57 int main()
58 {
59     Node node[7];
60     node[0].val = 8;
61     node[0].left = &node[1];
62     node[0].right = &node[2];
63 
64     node[1].val = 6;
65     node[1].left = &node[3];
66     node[1].right = &node[4];
67 
68     node[2].val = 10;
69     node[2].left = &node[5];
70     node[2].right = &node[6];
71 
72     node[3].val = 5;
73     node[4].val = 7;
74     node[5].val = 9;
75     node[6].val = 11;
76 
77     //convert(&node[0]);
78     stackConvert(&node[0]);
79 
80     print(&node[0]);
81     cout << endl;
82 
83     Node a[2];
84     a[0].val = 1;
85     a[0].left = &a[1];
86 
87     a[1].val = 2;
88 
89     //convert(&a[0]);
90     stackConvert(&a[0]);
91     print(&a[0]);
92 }
posted @ 2012-11-21 19:48  chkkch  阅读(336)  评论(0编辑  收藏  举报