1.因为二叉搜索树的特性,将preorder数组排序,得到inorder。再将inorder的元素和下标用map存储起来,再对其进行递归。 2.利用二叉树的特性,初始化最小值,最大值,进行递归 3.用栈结构进行迭代。 classSolution {int[] preorder;intidx = 0; Map<Integer, Integer> map_inorder =newHashMap<>();publicTreeNode...
classSolution{public:TreeNode*bstFromPreorder(vector<int>& preorder){if(preorder.empty())returnnullptr; TreeNode *node =newTreeNode(preorder[0]);inti =0, n = preorder.size();for(i =1; i < n; ++i) {if(preorder[i] > preorder[0])break; }vector<int>left(preorder.begin() +1...
105. Construct Binary Tree from Preorder and Inorder Traversal——tree,程序员大本营,技术文章内容聚合第一站。
889. Construct Binary Tree from Preorder and Postorder Traversal,程序员大本营,技术文章内容聚合第一站。
private TreeNode helper(int[] preorder, int preL, int preR, int[] inorder, int inL, int inR, HashMap<Integer, Integer> map) { if(preL>preR || inL>inR) return null; TreeNode root = new TreeNode(preorder[preL]); int index = map.get(root.val); ...
TreeNode *node=new TreeNode(preorder[pL]); vector<int>::iterator it=find(inorder.begin(),inorder.end(),preorder[pL]); int mid=it-inorder.begin(); if(mid==iL){ node->left=NULL; }else{ node->left=helper(preorder,pL+1,pL+(mid-iL),inorder,iL,mid-1); ...
preorder(root); printf("\ninorder traversal of tree\n"); inorder(root); printf("\npostorder traversal of tree\n"); postorder(root); break; case2: insert(); printf("\npreorder traversal of tree\n"); preorder(root); printf("\nInorder traversal of tree\n"); ...
标签: Tree, Array, Depth-first Search 相关题目: (M) Construct Binary Tree from Preorder and Inorder Traversal *//* MARK: - 题目英文: Given inorder and postorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. ...
Node*buildTree(auto&preorder,int&pIndex,intstart,intend,auto&map) { //指定されたプレオーダーシーケンスの次のアイテムを検討します。 //このアイテムは、によって形成されるサブツリーのルートノードになります // postorder[start、end] ...
packageLeetCode_1008/*** 1008. Construct Binary Search Tree from Preorder Traversal *https://leetcode.com/problems/construct-binary-search-tree-from-preorder-traversal/description/* * Return the root node of a binary search tree that matches the given preorder traversal. ...