Stan Cao

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LeetCodeNotes 167
Study Notes 16
SQL 1
Diary 1

LeetCodeNotes

LeetCode - The Stack Part

less than 1 minute read

The typical problems in LeetCode is the basic calculator series. The main idea is to use stack and read the input string from end to start if there’s bracket...

LeetCode - The Bit Manipulation Part

2 minute read

Single Number Problem

LeetCode - The Tree Part

3 minute read

The basic idea of tree related problems is to use recursion. If we can do it for left subtree and right subtree, we can do it for the whole tree.

LeetCode - The Two Pointers Part

less than 1 minute read

There are two types of two pointers.

LeetCode - The Search Part

less than 1 minute read

This part is for search part.

LeetCode - The Linked List Part

less than 1 minute read

Basically, we can use two approaches to solve linked list related problems. One is recursion, one is iteration. What we need to do is find the way we change ...

LeetCode - The DP Part

1 minute read

(reference)[https://oi-wiki.org/dp/]

LeetCode - The Backtrack Part

1 minute read

The backtrack is use to get all information of one path.

LeetCode - The Binary Search Part

2 minute read

This part is for Binary Search.

LeetCode - The Sliding Window Part

2 minute read

This part is Sliding Window related problems.

LeetCode - The Two Sum Part

less than 1 minute read

This part is Two Sum related problems.

LeetCode - Strobogrammatic Number III

1 minute read

Problem description

LeetCode - Sliding Window Maximum

2 minute read

Problem description

LeetCode - Shortest Word Distance II

1 minute read

Problem description

LeetCode - Different Ways to Add Parentheses

1 minute read

Problem description

LeetCode - Number of Digit One

1 minute read

Problem description

LeetCode - Majority Element II

1 minute read

Problem description

LeetCode - Lowest Common Ancestor of a Binary Tree

1 minute read

Problem description

LeetCode - Implement Queue using Stacks

3 minute read

Problem description

LeetCode - Basic Calculator

2 minute read

Problem description

LeetCode - Basic Calculator II

1 minute read

Problem description

LeetCode - The Skyline Problem

4 minute read

Problem description

LeetCode - Maximal Square

1 minute read

Problem description

LeetCode - Count Complete Tree Nodes

2 minute read

Problem description

LeetCode - Contains Duplicate III

1 minute read

Problem description

LeetCode - Contains Duplicate II

1 minute read

Problem description

LeetCode - Word Search II

3 minute read

Problem description

LeetCode - Shortest Palindrome

1 minute read

Problem description

LeetCode - House Robber II

1 minute read

Problem description

LeetCode - Add and Search Word Data Structure Design

1 minute read

Problem description

LeetCode - Remove Linked List Elements

less than 1 minute read

Problem description

LeetCode - Number of 1 Bits

1 minute read

Problem description

LeetCode - Minimum Size Subarray Sum

1 minute read

Problem description

LeetCode - Count Primes

1 minute read

Problem description

LeetCode - Repeated DNA Sequences

less than 1 minute read

Problem description

LeetCode - Largest Number

1 minute read

Problem description

LeetCode - Best Time to Buy and Sell Stock IV

1 minute read

Problem description

LeetCode - Majority Element

1 minute read

Problem description

LeetCode - Fraction to Recurring Decimal

1 minute read

Problem description

LeetCode - Missing Ranges

1 minute read

Problem description

LeetCode - Min Stack

3 minute read

Problem description

LeetCode - Maximum Gap

2 minute read

Problem description

LeetCode - Intersection Of Two Linked Lists

1 minute read

Problem description

LeetCode - Find Minimum in Rotated Sorted Array II

1 minute read

Problem description

LeetCode - Binary Tree Upside Down

2 minute read

Problem description

LeetCode - Maximum Product Subarray

1 minute read

Problem description

LeetCode - Max Points on a Line

1 minute read

Problem description

LeetCode - Find Minimum in Rotated Sorted Array

1 minute read

Problem description

LeetCode - Sort List

1 minute read

Problem description

LeetCode - Reorder List

1 minute read

Problem description

LeetCode - Insertion Sort List

1 minute read

Problem description

LeetCode - Word Break

1 minute read

Problem description

LeetCode - Word Break II

1 minute read

Problem description

LeetCode - Copy List with Random Pointer

2 minute read

Problem description

LeetCode - Word Ladder

3 minute read

Problem description

LeetCode - Two City Scheduling

1 minute read

Problem description

LeetCode - Surrounded Regions

2 minute read

Problem description

LeetCode - Palindrome Partitioning

2 minute read

Problem description

LeetCode - Palindrome Partitioning II

1 minute read

Problem description

LeetCode - Longest Consecutive Sequence

1 minute read

Problem description

LeetCode - Gas Station

2 minute read

Problem description

LeetCode - Clone Graph

2 minute read

Problem description

LeetCode - Candy

3 minute read

Problem description

LeetCode - Word Ladder II

3 minute read

Problem description

LeetCode - Populating Next Right Pointers in Each Node

2 minute read

Problem description

LeetCode - Populating Next Right Pointers in Each Node II

1 minute read

Problem description

LeetCode - Distinct Subsequences

3 minute read

Problem description

LeetCode - Binary Tree Maximum Path Sum

2 minute read

Problem description

LeetCode - Best Time to Buy and Sell Stock

1 minute read

Problem description

LeetCode - Best Time to Buy and Sell Stock III

1 minute read

Problem description

LeetCode - Best Time to Buy and Sell Stock II

2 minute read

Problem description

LeetCode - Flatten Binary Tree to Linked List

1 minute read

Problem description

LeetCode - Convert Sorted List to Binary Search Tree

1 minute read

Problem description

LeetCode - Construct Binary Tree from Preorder and Inorder Traversal

1 minute read

Problem description

LeetCode - Construct Binary Tree from Inorder and Postorder Traversal

1 minute read

Problem description

LeetCode - Balanced Binary Tree

1 minute read

Problem description

LeetCode - Validate Binary Search Tree

2 minute read

Problem description

LeetCode - Unique Binary Search Trees

1 minute read

Problem description

LeetCode - Unique Binary Search Trees II

1 minute read

Problem description

LeetCode - Restore IP Addresses

1 minute read

Problem description

LeetCode - Recover Binary Search Tree

1 minute read

Problem description

LeetCode - Interleaving String

4 minute read

Problem description

LeetCode - Binary Tree Level Order Traversal

2 minute read

Problem description

LeetCode - Subsets II

less than 1 minute read

Problem description

LeetCode - Search in Rotated Sorted Array II

1 minute read

Problem description

LeetCode - Scramble String

2 minute read

Problem description

LeetCode - Reverse Linked List II

1 minute read

Problem description

LeetCode - Remove Duplicates from Sorted List II

less than 1 minute read

Problem description

LeetCode - Partition List

1 minute read

Problem description

LeetCode - Merge Sorted Array

1 minute read

Problem description

LeetCode - Maximal Rectangle

1 minute read

Problem description

LeetCode - Largest Rectangle in Histogram

4 minute read

Problem description

LeetCode - Gray Code

1 minute read

Problem description

LeetCode - Decode Ways

1 minute read

Problem description

LeetCode - Word Search

1 minute read

Problem description

LeetCode - Subsets

less than 1 minute read

Problem description

LeetCode - Sort Colors

1 minute read

Problem description

LeetCode - Set Matrix Zeroes

2 minute read

Problem description

LeetCode - Search a 2D Matrix

1 minute read

Problem description

LeetCode - Remove Duplicates from Sorted Array II

1 minute read

Problem description

LeetCode - Minimum Window Substring

1 minute read

Problem description

LeetCode - Edit Distance

1 minute read

Problem description

LeetCode - Combinations

1 minute read

Problem description

LeetCode - Text Justification

2 minute read

Problem description

LeetCode - Sqrt X

1 minute read

Problem description

LeetCode - Simplify Path

1 minute read

Problem description

LeetCode - Valid Number

2 minute read

Problem description

LeetCode - Unique Path

1 minute read

Problem description

LeetCode - Unique Paths II

1 minute read

Problem description

LeetCode - Rotate List

2 minute read

Problem description

LeetCode - Permutation Sequence

1 minute read

Problem description

LeetCode - Spiral Matrix

2 minute read

Problem description

LeetCode - Merge Intervals

1 minute read

Problem description

LeetCode - Maximum Subarray

2 minute read

Problem description

LeetCode - Jump Game

less than 1 minute read

Problem description

LeetCode - Insert Interval

less than 1 minute read

Problem description

LeetCode - N Queues

6 minute read

Problem description

LeetCode - Rotate Image

1 minute read

Problem description

LeetCode - Pow(x, n)

2 minute read

Problem description

LeetCode - Permutations

less than 1 minute read

Problem description

LeetCode - Permutations II

1 minute read

Problem description

LeetCode - Group Anagrams

less than 1 minute read

Problem description

LeetCode - Jump Game II

1 minute read

Problem description

LeetCode - Wildcard Matching

3 minute read

Problem description

LeetCode - Multiply Strings

2 minute read

Problem description

LeetCode - Trapping Rain Water

1 minute read

Problem description

LeetCode - First Missing Positive

1 minute read

Problem description

LeetCode - Combination Sum II

1 minute read

Problem description

LeetCode - Sudoku Solver

4 minute read

Problem description

LeetCode - Combination Sum

1 minute read

Problem description

LeetCode - Valid Sudoku

2 minute read

Problem description

LeetCode - Substring with Concatenation of All Words

3 minute read

Problem description

LeetCode - Search Insert Position

1 minute read

Problem description

LeetCode - Search in Rotated Sorted Array

2 minute read

Problem description

LeetCode - Remove Element

2 minute read

Problem description

LeetCode - Remove Duplicates from Sorted Array

1 minute read

Problem description

LeetCode - Next Permutation

2 minute read

Problem description

LeetCode - Longest Valid Parentheses

2 minute read

Problem description

LeetCode - Implement strStr()

3 minute read

Problem description

LeetCode - Find First and Last Position of Element in Sorted Array

2 minute read

Problem description

LeetCode - Divide Two Integers

1 minute read

Problem description

LeetCode - Count and Say

1 minute read

Problem description

LeetCode - Valid Parentheses

1 minute read

Problem description

LeetCode - Swap Nodes in Pairs

1 minute read

Problem description

LeetCode - Reverse Nodes in k-Group

1 minute read

Problem description

LeetCode - Remove Nth Node From End of List

1 minute read

Problem description

LeetCode - Merge Two Sorted Lists

1 minute read

Problem description

LeetCode - Merge k Sorted Lists

2 minute read

Problem description

LeetCode - Generate Parentheses

less than 1 minute read

Problem description

LeetCode - Letter Combinations of a Phone Number

2 minute read

Problem description

LeetCode - 4Sum

4 minute read

Problem description

LeetCode - 3Sum Closest

1 minute read

Problem description

LeetCode - 3Sum

1 minute read

Problem description

LeetCode - Roman to Integer

3 minute read

Problem description

LeetCode - Longest Common Prefix

1 minute read

Problem description

LeetCode - String to Integer (atoi)

4 minute read

Problem description

LeetCode - Regular Expression Matching

2 minute read

Problem description

LeetCode - Palindrome Number

1 minute read

Problem description

LeetCode - Integer to Roman

2 minute read

Problem description

LeetCode - Container With Most Water

2 minute read

Problem description

LeetCode - ZigZag Conversion

3 minute read

Problem description

LeetCode - Reverse Integer

1 minute read

Problem description

LeetCode - Median of Two Sorted Arrays

1 minute read

Problem description

LeetCode - Longest Substring Without Repeating Characters

2 minute read

Problem description

LeetCode - Longest Palindromic Substring

2 minute read

Problem description

LeetCode - Add Two Numbers

1 minute read

Problem description

LeetCode - Two Sum

1 minute read

Problem description

Study Notes

K-D-tree

1 minute read

A k-dimensional or k-d tree is a binary tree used to subdivide a collection of records into ranges for k diﬀerent attributes in each record.

B-tree

2 minute read

In the 1980s B-trees were applied to database management systems, with an emphasis on how to ensure consistent B-tree access patterns to support concurrency ...

Sorting

1 minute read

Sorting is always an important topic in computer science. Theoretically, comparison sorts cannot perform better than O(n lgn) in the best case, better perfor...