[LeetCode] Construct Binary Tree from Preorder and Inorder Traversal

Given preorder and inorder traversal of a tree, construct the binary tree.

Note:
You may assume that duplicates do not exist in the tree.

/** * Definition for binary tree * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode(int x) { val = x; } * } */public class Solution {    public TreeNode buildTree(int[] preorder, int[] inorder) {return build(inorder, 0, inorder.length - 1, preorder, 0, preorder.length - 1);}public TreeNode build(int[] inorder, int lo1, int hi1, int[] preorder, int lo2, int hi2) {if (lo2 > hi2) return null;int index = getIndex(inorder, preorder[lo2]);TreeNode root = new TreeNode(preorder[lo2]);root.left = build(inorder, lo1, index - 1, preorder, lo2 + 1, lo2 + 1 + ((index - 1) - lo1));root.right = build(inorder, index + 1, hi1, preorder,lo2 + 1 + ((index - 1) - lo1) + 1, lo2 + 1 + ((index - 1) - lo1) + 1 + (hi1 - (index + 1)));return root;}public int getIndex(int[] array, int val) {for (int i = 0; i < array.length; i++) {if (array[i] == val) return i;}return -1;}}