LeetCode Playground & Binary Tree Traversal All In One

LeetCode Playground & Binary Tree Traversal All In One

非正常的二叉搜索树/排序二叉树生成

// binary-tree-generator.ts 不好使

// 手动生成 ✅ 非正常的二叉搜索树/排序二叉树
const node = new TreeNode(1);
node.right = new TreeNode(2);
node.right.left = new TreeNode(3);
console.log(`node =`, node);

https://www.cnblogs.com/xgqfrms/p/17052456.html#5141281

Binary Tree Traversal / 二叉树遍历

// 手动生成 ✅ 非正常的二叉搜索树/排序二叉树
const node = new TreeNode(1);
node.right = new TreeNode(2);
node.right.left = new TreeNode(3);
console.log(`node =`, node);


function preorderTraversal(root: TreeNode | null): number[] {
  if(!root) return [];
  // DFS 深度优先搜索
  function dfs(head: TreeNode | null, result: number[]) {
    if(!head) {
      return;
    }
    // 先序遍历
    result.push(head.val);
    dfs(head.left, result)
    dfs(head.right, result);
  }
  let result: number[] = [];
  dfs(root, result);
  return result;
};

const preorder = preorderTraversal(node);
console.log(`preorder tree =`, preorder);

function inorderTraversal(root: TreeNode | null): number[] {
  if(!root) return [];
  // DFS 深度优先搜索
  function dfs(head: TreeNode | null, result: number[]) {
    if(!head) {
      return;
    }
    dfs(head.left, result)
    // 中序遍历
    result.push(head.val);
    dfs(head.right, result);
  }
  let result: number[] = [];
  dfs(root, result);
  return result;
};

const tree = inorderTraversal(node);
console.log(`inorder tree =`, tree);

function postorderTraversal(root: TreeNode | null): number[] {
  if(!root) return [];
  // DFS 深度优先搜索
  function dfs(head: TreeNode | null, result: number[]) {
    if(!head) {
      return;
    }
    dfs(head.left, result)
    dfs(head.right, result);
    // 后序遍历
    result.push(head.val);
  }
  let result: number[] = [];
  dfs(root, result);
  return result;
};

const postorder = postorderTraversal(node);
console.log(`post tree =`, postorder);

https://leetcode.com/playground/7wyqA5aJ

(🐞 反爬虫测试！打击盗版⚠️）如果你看到这个信息, 说明这是一篇剽窃的文章，请访问 https://www.cnblogs.com/xgqfrms/ 查看原创文章！

refs

https://stackfull.dev/tree-data-structure-in-javascript

---

---

©xgqfrms 2012-2021

www.cnblogs.com/xgqfrms 发布文章使用：只允许注册用户才可以访问！

原创文章，版权所有©️xgqfrms, 禁止转载 🈲️，侵权必究⚠️！

---