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• LintCode Binary Tree 29
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LintCode Binary Tree

Maximum Depth of Binary Tree

1 minute read

Given a binary tree, find its maximum depth.

Binary Tree Level Order Traversal

1 minute read

Level Order Traversal

Binary Tree Postorder Traversal

1 minute read

Postorder Traversal

Binary Tree Inorder Traversal

1 minute read

Inorder Traversal

Convert BST to Greater Tree

1 minute read

Given a Binary Search Tree (BST), convert it to a Greater Tree such that every key of the original BST is changed to the original key plus sum of all keys gr...

Binary Tree Preorder Traversal

1 minute read

Preorder Traversal

Binary Tree Longest Consecutive Sequence

1 minute read

Given a binary tree, find the length of the longest consecutive sequence path.

Binary Tree Paths

1 minute read

Given a binary tree, return all root-to-leaf paths.

Lowest Common Ancestor II

1 minute read

Given the root and two nodes in a Binary Tree. Find the lowest common ancestor(LCA) of the two nodes.

Same Tree

1 minute read

Check if two binary trees are identical. Identical means the two binary trees have the same structure and every identical position has the same value.

Flatten Binary Tree to Linked List

1 minute read

Flatten a binary tree to a fake “linked list” in pre-order traversal.

Binary Tree Path Sum

1 minute read

Given a binary tree, find all paths that sum of the nodes in the path equals to a given number target.

Clone Binary Tree

less than 1 minute read

For the given binary tree, return a deep copy of it.

Convert Binary Tree to Linked Lists by Depth

1 minute read

Given a binary tree, design an algorithm which creates a linked list of all the nodes at each depth.

Insert Five

1 minute read

Given a number, insert a 5 at any position of the number to make the number after insertion the largest

Binary Tree Postorder Traversal-null

1 minute read

Given a binary tree, return the postorder traversal of its nodes’ values. (Iteratively)

Convert Sorted Array to Binary Search Tree With Minimal Height

1 minute read

Given a sorted (increasing order) array, Convert it to create a binary search tree with minimal height.

Invert Binary Tree

less than 1 minute read

Invert a binary tree. Left and right subtrees exchange.

Minimum Depth of Binary Tree

2 minute read

Given a binary tree, find its minimum depth.

N-ary Tree Preorder Traversal

1 minute read

Given an n-ary tree, return the preorder traversal of its nodes’ values.

Leaf-Similar Trees

1 minute read

Consider all the leaves of a binary tree. From left to right order, the values of those leaves form a leaf value sequence.

Sum of Left Leaves

1 minute read

Find the sum of all left leaves in a given binary tree.

Binary Tree Tilt

1 minute read

Given a binary tree, return the tilt of the whole tree.

Subtree of Another Tree

2 minute read

Given two non-empty binary trees s and t, check whether tree t has exactly the same structure and node values with a subtree of s.

Average of Levels in Binary Tree

1 minute read

Given a non-empty binary tree, return the average value of the nodes on each level in the form of an array.

Maximum Binary Tree

1 minute read

Construct the maximum tree by the given array and return the root node of this tree.

Second Minimum Node In a Binary Tree

1 minute read

Output the second minimum value in the set made of all the nodes’ value in the whole tree.

Minimum Difference Between BST Nodes

1 minute read

Given a Binary Search Tree (BST) with the root node root, return the minimum difference between the values of any two different nodes in the tree.

Binary Tree Pruning

1 minute read

Return this tree where every subtree (of the given tree) not containing a 1 has been removed.

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LeetBook Easy Mode

Contains Duplicate

1 minute read

Question

Single Number

less than 1 minute read

Question

Rotate Array

1 minute read

Question

Best Time to Buy and Sell Stock

1 minute read

Question

Remove Duplicates from Sorted Array

2 minute read

Question

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LeetCode Top 100

Reverse Linked List

less than 1 minute read

Reverse a singly linked list.

Add Two Numbers

1 minute read

Add the two numbers and return it as a linked list. Question

Two Sum

1 minute read

Return indices of the two numbers such that they add up to a specific target. Question

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DP

House Robber III

2 minute read

Rob the most amount of money.

House Robber II

2 minute read

Rob the most amount of money.

House Robber

1 minute read

Rob the most amount of money.

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SQL

Row & Column Swap Template

less than 1 minute read

Row_Column_Swap_Template

Get Top N

less than 1 minute read

How To Get Top N Diff Between Rank, Dense_Rank, and Row_Number

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