Given preorder and inorder traversal of a tree, construct the binary tree.
Note:
You may assume that duplicates do not exist in the tree.
给出树的前序和中序遍历序列，构造二叉树，假设树唯一存在。
剑指offer面试题6，重建二叉树
leetcode之Construct Binary Tree from Preorder and Inorder Traversal
原文：http://www.cnblogs.com/gracyandjohn/p/4574253.html