TREEORD - Tree _order

Description

A tree is a connected acyclic graph.
A binary tree is a tree for which each node has a left child, a right child, both, or neither, e.g.
    1
   / \
  2   3
 / \   \
4   5   6
There are three common ways to recursively traverse such a tree.
  1. Pre-order: parent, left subtree, right subtree
  2. Post-order: left subtree, right subtree, parent
  3. In-order: left subtree, parent, right subtree
Given pre-order, post-order, and in-order traversals, determine if they can be of the same binary tree.
For example,
1 2 4 5 3 6
4 5 2 6 3 1
4 2 5 1 3 6
are the pre-order, post-order, and in-order traversals of the tree above.
But
1 2 4 5 3 6
4 5 2 6 1 3
4 2 5 1 6 3
cannot be the pre-order, post-order, and in-order traversals of the same binary tree.

Input

The first line is the number of nodes in each traversal, 0 < N <= 8000.
The second line is the N space separated nodes of the pre-order traversal.
The third line is the N space separated nodes of the post-order traversal.
The fourth line is the N space separated nodes of the in-order traversal.
Each traversal is a sequence of the nodes, numbered 1 to N, without repetition.

Output

Print "yes" if all three traversals can be of the same tree, and "no" otherwise.
Input Input
6
1 2 4 5 3 6
4 5 2 6 3 1
4 2 5 1 3 6
6
1 2 4 5 3 6
4 5 2 6 1 3
4 2 5 1 6 3
Output Output
yes
no

Added by:BYU Admin
Date:2014-02-23
Time limit:0.5s-3s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64

hide comments
2016-08-04 06:57:48
I found it tricky. Finally AC.
2016-06-30 20:50:36 kartikay singh
Nice problem :-)
Easy recursion
2016-04-09 14:20:36
y
2016-04-07 14:12:42
Sesi Lab, ez :v

Last edit: 2016-04-07 14:27:26
2016-04-07 14:09:54
AC in one go. Nice problem. Think of recursion ;D
2016-02-26 11:04:52 Archit Gupta
AC in first attempt easy prob 150th on spoj!
2016-01-02 12:03:35 :.Mohib.:
Like it...!!
2015-10-10 19:22:59 kejriwal
nice and elegant (: !!
2015-08-21 11:19:38 Jaswanth
nice concept on trees.
2015-07-06 10:11:25
AC :)
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