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Write a program which reads two sequences of nodes obtained by the preorder tree walk and the inorder tree walk on a binary tree respectively, and prints a sequence of the nodes obtained by the postorder tree walk on the binary tree.

Input

In the first line, an integer nn, which is the number of nodes in the binary tree, is given.

In the second line, the sequence of node IDs obtained by the preorder tree walk is given separated by space characters. In the second line, the sequence of node IDs obtained by the inorder tree walk is given separated by space characters.

Every node has a unique ID from 11 to nn. Note that the root does not always correspond to 11.

Output

Print the sequence of node IDs obtained by the postorder tree walk in a line. Put a single space character between adjacent IDs.

Constraints

• 1≤n≤401≤n≤40

Sample Input 1

51 2 3 4 53 2 4 1 5

Sample Output 1

3 4 2 5 1

Sample Input 2

41 2 3 41 2 3 4

Sample Output 2

4 3 2 1

 给出先序遍历和中序遍历，求后序遍历。

可以通过遍历先序，确定节点的左右子树，然后求解。

代码如下：

 

#include 
   
    #include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;int n;int loc=0;vector 
        
          pre,in,post;int finds (int x){ for (int i=0;i
         
          =r) return; int root=pre[loc++]; int m=finds(root); rec(l,m); rec(m+1,r); post.push_back(root);}void output (){ rec (0,n); for (int i=0;i
         
        
       
      
     
    
   

 

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