104. Construct Binary Tree from Preorder and Inorder Traversal

这道题与 [77. Construct Binary Tree from Inorder and Postorder Traversal](../77. Construct Binary Tree from Inorder and Postorder Traversal) 的思路几乎一模一样。

所以不多做赘述了，解法上也没有太多创新，考点依旧是对二叉树深度遍历的理解。