left.right = Node(5) print("Preorder traversal of binary tree is") printPreorder(root) print("\nInorder traversal of binary tree is") printInorder(root) print("\nPostorder traversal of binary tree is") printPos
65publicstaticvoidinOrder(TreeNode root){66if(root ==null)return;67inOrder(root.left);68visit(root);69inOrder(root.right);70}7172publicstaticvoidinOrder2(TreeNode root){73if(root ==null)return;74Stack<TreeNode> stack =newStack<TreeNode>();75while(!stack.empty() || root !=null){76...
for inorder and level order tranvese, we needs to use a cur pointer on root but for pre and post order, we only needs to push the root. Core statement: while statement: preorder: while stack is not empty: pop() and added cur.val, stack.pop(cur.right) stack.pop(cur.left) postor...
更为简洁非递归解法 具体程序如下: 1vector<int> preorderTraversal(TreeNode*root) {2vector<int>rVec;3if(!root)4returnrVec;56stack<TreeNode *>st;7st.push(root);8while(!st.empty())9{10TreeNode *tree =st.top();11rVec.push_back(tree->val);12st.pop();13if(tree->right)14st.push(...
Tree Tranverse: Pre/In/Post/Level Order tranverse Preorder: 迭代写法: class Solution { public List<Integer> preorderTraversal(TreeNode root) { List<Integer> res = new ArrayList<>(); if(root == null) return res; //we need to check it is null or not...
Inorder 方法一:和Preorder方法一类似,直接做,但是需要一个计数器,第二次出栈的时候才可以输出。 classSolution {public: vector<int> inorderTraversal(TreeNode*root) { vector<int>res;if(root==NULL)returnres; unordered_map<TreeNode *,int> hash;//default value is 0;stack<TreeNode *>s({root})...
preorderTraversal(result, root.right); } public void postorderTraversal(List<Integer> result, TreeNode root){ if(root==null) return; postorderTraversal(result, root.left); postorderTraversal(result, root.right); result.add(root.val);
144. Binary Tree Preorder Traversal 94. Binary Tree Inorder Traversal 145. Binary Tree Postorder Traversal 前序排列 :根-左-右 中序排列: 左-根-右 后序排列:左-右-根 参考答案 1 // PreOrder 2 /** 3 * Definition for a binary tree node. 4 * struct TreeNode { 5 * int val; 6 ...
但是inorder不简单啊,模仿递归记录调用处然后处理完当前函数回来,下午困得不行闷头试了好几次各种bug超Memory,看了我是歌手回来发现脑子清醒了 1vector<int> inorderTraversal(TreeNode *root) {2vector<int>nodes;3if(root == NULL)returnnodes;4stack<TreeNode *>tStack;5TreeNode * cur =root;6while(!tS...
Implement common Depth-First Traversal (DFS) patterns with recursion and learn about the call stack in this visual guide.def in_order(root=None): if root: in_order(root.left) print(root.val) in_order(root.right) def pre_order(root=None): if root: print(root.val) pre_...