inorder,(long)Integer.MAX_VALUE+1);}intpre=0;intin=0;privateTreeNodebuildTreeHelper(int[]preorder,int[]inorder,longstop){//到达末尾返回 nullif(pre==preorder.length){returnnull;}//到达停止点返回 null//当前停止点已经用了,in 后
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...
root->left=newTreeNode(preorder[left]); dfs(preorder,root->left,left+1,i-1); } } } TreeNode*bstFromPreorder(vector<int>&preorder) { intlen=preorder.size(); TreeNode*root=newTreeNode(preorder[0]); dfs(preorder,root,1,len-1); returnroot; } }; 1. 2. 3. 4. 5. 6. 7....
}privateTreeNode buildTree(int[] preorder,intpreLo,intpreHi,int[] inorder,intinLo,intinHi) {if(preLo > preHi || inLo >inHi)returnnull; TreeNode root=newTreeNode(preorder[preLo]);introotAtInorder = 0;for(inti = inLo; i <= inHi; i++) {if(inorder[i] == root.val) {//...
LeetCode Top 100 Liked Questions 105. Construct Binary Tree from Preorder and Inorder Traversal (Java版; Medium) 题目描述 Given preorder and inorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. ...
intsearchNode(intinorder[],intinorderSize,intkey){inti;for(i=0;i<inorderSize;i++){if(key==inorder[i]){returni;}}return-1;}structTreeNode*buildTree(int*preorder,intpreorderSize,int*inorder,intinorderSize){if(preorder==NULL||inorder==NULL||preorderSize==0||inorderSize==0)return...
* TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */publicclassSolution{public TreeNodebuildTree(int[]preorder,int[]inorder){if(preorder==null||preorder.length==0)returnnull;if(inorder==null||inorder.length==0)returnnull;if(preorder.length!=inorder.length...
preorder traversal of a tree * @param inorder: A list of integers that inorder traversal of a tree * @return: Root of a tree */ public void main(String[] args){ int[] A= new int[] {2,1,3} ; int[] B = new int[] {1,2,3}; TreeNode root = buildTree(A , B) ; ...
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。
(preBegin == preEnd) return nullptr; //从中序遍历结果中找出根节点(根节点在前序遍历中是第一个节点) vector<int>::iterator itRoot = find(inBegin, inEnd, *preBegin); TreeNode *root = new TreeNode(*itRoot); //计算根的左子树节点个数 int leftSize = itRoot - inBegin; //在中序遍历...