1 #include <iostream>
2 #include<cstdio>
3 #include <string>
4 using namespace std;
5 struct Node{
6 char data;
7 Node* lchild;
8 Node* rchild;
9 };
10 Node* CreateTree(string pre,string in)
11 {
12 Node* root = NULL;
13 if(pre.length()>0)
14 {
15 root = new Node;
16 root->data = pre[0];
17 int index = in.find(root->data);
18 root->lchild = CreateTree(pre.substr(1,index),in.substr(0,index));
19 root->rchild = CreateTree(pre.substr(index+1),in.substr(index+1));
20 }
21 return root;
22 }
23
24 void PostOrder(Node* root)
25 {
26 if(root!=NULL)
27 {
28 PostOrder(root->lchild);
29 PostOrder(root->rchild);
30 cout<<root->data;
31 }
32 }
33
34 int main()
35 {
36 string pre_str,in_str;
37 while (cin>>pre_str>>in_str)
38 {
39 Node* rt = CreateTree(pre_str,in_str);
40 PostOrder(rt);
41 cout<<endl;
42 }
43 }
