PROGRAMMING:Output preorder traversal according to postorder and middle order traversal
This problem requires that according to a given binary tree after order traversal and in order traversal results, the output of the tree's preorder traversal results.
###Input format:
The first line gives the positive integer $$n $$($$Le 30 $$), which is the number of nodes in the tree. In the next two lines, $$n $$integers are given in each line, corresponding to the results of post order traversal and middle order traversal respectively, and the numbers are separated by spaces. Ensure that the correct input corresponds to a binary tree.
###Output format:
Output 'preorder:' and the result of preorder traversal of the tree in one line. There should be one space between the numbers and no extra space at the end of the line.
###Input example:
```in
seven
2 3 1 5 7 6 4
1 2 3 4 5 6 7
```
###Output example:
```out
Preorder: 4 1 3 2 6 5 7
```
answer：If there is no answer, please comment
###Input format:
The first line gives the positive integer $$n $$($$Le 30 $$), which is the number of nodes in the tree. In the next two lines, $$n $$integers are given in each line, corresponding to the results of post order traversal and middle order traversal respectively, and the numbers are separated by spaces. Ensure that the correct input corresponds to a binary tree.
###Output format:
Output 'preorder:' and the result of preorder traversal of the tree in one line. There should be one space between the numbers and no extra space at the end of the line.
###Input example:
```in
seven
2 3 1 5 7 6 4
1 2 3 4 5 6 7
```
###Output example:
```out
Preorder: 4 1 3 2 6 5 7
```
answer：If there is no answer, please comment