System.out.println(Main28.preorderTraversal(root)); } publicstaticclassTreeNode { intval; TreeNode left; TreeNode right; TreeNode(intx) { val = x; } } //非递归 staticArrayList<Integer> array =newArrayList<>();//[4
*/// 由于主函数的形式已经符合分治法需要的形式(具有合适的返回值),直接使用主函数做为递归函数vector<int>preorderTraversal(TreeNode * root){//递归三要素之定义// write your code herevector<int> result;if(root == nullptr) {returnresult;// 递归三要素之出口}// 获取左子树的遍历结果vector<int> ...
classSolution {public: vector<int> preorderTraversal(TreeNode *root) { vector<int>res; stack<TreeNode *>s;if(root == NULL){//空树returnres; } s.push(root);//放树根while(!s.empty()){ TreeNode*cc =(); s.pop(); res.push_back(cc->val);//访问根if(cc->right !=NULL){ s.p...
12 vector<int> preorderTraversal(TreeNode *root) { 13 vector<int> v; 14 if(root==NULL) 15 return v; 16 stack<TreeNode *> tree; 17 tree.push(root); 18 while(!tree.empty()){ 19 TreeNode *p=tree.top(); 20 v.push_back(p->val); 21 tree.pop(); 22 if(p->right!=NULL) 2...
public List<Integer> preorderTraversal(TreeNode root) { List<Integer> list = new ArrayList<>(); preorderTraversalHelper(root, list); return list; } private void preorderTraversalHelper(TreeNode root, List<Integer> list) { if (root == null) { return; } list.add(root.val); preorderTrav...
Construct Binary Tree from Preorder and Inorder Traversal 题目描述(中等难度) 根据二叉树的先序遍历和中序遍历还原二叉树。 解法一 递归 先序遍历的顺序是根节点,左子树,右子树。中序遍历的顺序是左子树,根节点,右子树。 所以我们只需要根据先序遍历得到根节点,然后在中序遍历中找到根节点的位置,它的左边就...
15、课程:树(下).10、练习—Iterative Postorder Traversal -- -- 10:33 App 15、课程:树(下).7、练习—Iterative Get和Iterative Add 2 -- 12:36 App 15、课程:树(下).13、练习—Construct Binary Tree from Preorder and Inorder Traversal 1 -- 9:07 App 15、课程:树(下).3、练习—Floor and...
The pre-order and post-order traversal of a Binary Tree is A 、B 、C and C 、B 、A, respectively. The number of trees that satisfy the conditions is . A.1 B.2 C.3 D.4 暂无答案
The pre-order and post-order traversal of a Binary Tree generates the same output. The tree can have maximum . A、Three nodes B、Two nodes C、One node D、Any number of nodes 暂无答案
*/classSolution{public List<Integer>preorderTraversal(TreeNode root){List<Integer>result=newLinkedList<>();TreeNode current=root;TreeNode prev=null;while(current!=null){if(current.left==null){result.add(current.val);current=current.right;}else{// has left, then find the rightmost of left su...