LeetCode - 106. Construct Binary Tree from Inorder and Postorder Traversal

这道题目的思路与上一题基本是一样的，就不再详细写出，代码如下：

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode(int x) { val = x; } * } */public class Solution {    public TreeNode buildTreeInPost(int preEnd, int inStart, int inEnd, int[] inorder, int[] postorder){        if(preEnd < 0 || inStart > inEnd) return null;                TreeNode root = new TreeNode(postorder[preEnd]);        int inIndex = 0;        // index of root in postorder        for(int i = inStart; i <= inEnd; i++){            if(inorder[i] == root.val) inIndex = i;        }        root.left = buildTreeInPost(preEnd - (inEnd - inIndex) - 1, inStart, inIndex - 1, inorder, postorder);        root.right = buildTreeInPost(preEnd - 1, inIndex + 1, inEnd, inorder, postorder);        return root;    }        public TreeNode buildTree(int[] inorder, int[] postorder) {        return buildTreeInPost(postorder.length - 1, 0, inorder.length - 1, inorder, postorder);    }}