Problem of The Day: Next Greater Element II
Problem Statement
Journal
2024
Problem of The Day: Find Building Where Alice and Bob Can Meet
Problem Statement
Problem of The Day: Reverse Odd Levels of Binary Tree
Problem Statement
Problem of The Day: Final Prices With a Special Discount in a Shop
Problem Statement
Problem of The Day: Continuous Subarrays
Problem Statement
Problem of The Day: Find Score of an Array After Marking All Elements
Problem Statement
Problem of The Day: Take Gifts From the Richest Pile
Problem Statement
Problem of The Day: Maximum Beauty of an Array After Applying Operation
Problem Statement
Problem of The Day: Find Longest Special Substring That Occurs Thrice I
Problem Statement
Problem of The Day: Two Best Non-Overlapping Events
Problem Statement
Problem of The Day: Special Array II
Problem Statement
Problem of The Day: Shortest Distance After Road Addition Queries I
Problem Statement
Problem of The Day: Maximum Number of Integers to Choose From a Range I
Problem Statement
Problem of The Day: Move Pieces to Obtain a String
Problem Statement
Problem of The Day: Make String a Subsequence Using Cyclic Increments
Problem Statement
Problem of The Day: Adding Spaces to a String
Problem Statement
Problem of The Day: Check If N and Its Double Exist
Problem Statement
Problem of The Day: The Maze II
Problem Statement
Problem of The Day: Minimum Obstacle Removal to Reach Corner
Problem Statement
Problem of The Day: Find Champion II
Problem Statement
Problem of The Day: Maximum Matrix Sum
Problem Statement
Problem of The Day: Rotating the Box
Problem Statement
Problem of The Day: Maximum Sum of Distinct Subarrays With Length K
Problem Statement
Problem of The Day: Defuse the Bomb
Problem Statement
Problem of The Day: Find the Power of K-Size Subarrays I
Problem Statement
Problem of The Day: Prime Subtraction Operation
Problem Statement
Problem of The Day: Prime Subtraction Operation
Problem Statement
Problem of The Day: Most Beautiful Item for Each Query
Problem Statement
Problem of The Day: The Number of the Smallest Unoccupied Chair
Problem Statement
Problem of The Day: Shortest Subarray With OR at Least K II
Problem Statement
Problem of The Day: Minimum Array End
Problem Statement
Problem of The Day: Maximum XOR for Each Query
Problem Statement
Problem of The Day: Find if Array Can Be Sorted
Problem Statement
Problem of The Day: String Compression III
Problem Statement
Problem of The Day: Circular Sentence
Problem Statement
Problem of The Day: Delete Characters to Make Fancy String
Problem Statement
Problem of The Day: Maximum Number of Moves in a Grid
Problem Statement
Problem of The Day: Longest Square Streak in an Array
Problem Statement
Problem of The Day: Count Square Submatrices with All Ones
Problem Statement
Problem of The Day: Remove Sub-Folders from the Filesystem
Problem Statement
Problem of The Day: Cousins in Binary Tree II
Problem Statement
Problem of The Day: Kth Largest Sum in a Binary Tree
Problem Statement
Problem of The Day: Find Kth Bit in Nth Binary String
Problem Statement
Problem of The Day: Count Number of Maximum Bitwise-OR Subsets
Problem Statement
Problem of The Day: Maximum Swap
Problem Statement
Problem of The Day: Longest Happy String
Problem Statement
Problem of The Day: Maximal Score After Applying K Operations
Problem Statement
Problem of The Day: Smallest Range Covering Elements from K Lists
Problem Statement
Problem of The Day: Minimum Add to Make Parentheses Valid
Problem Statement
Problem of The Day: Minimum Number of Swaps to Make the String Balanced
Problem Statement
Problem of The Day: Minimum String Length After Removing Substrings
Problem Statement
Problem of The Day: Sentence Similarity III
Problem Statement
Problem of The Day: Permutation in String
Problem Statement
Problem of The Day: Minimum Add to Make Parentheses Valid
Problem Statement
Problem of The Day: Diagonal Traverse
Problem Statement
Problem of The Day: Maximum Swap
Problem Statement
Problem of The Day: Shortest Path in Binary Matrix
Problem Statement
Problem of The Day: Shortest Path in Binary Matrix
Problem Statement
Problem of The Day: My Calendar II
Problem Statement
Problem of The Day: Design Circular Deque
Problem Statement
Problem of The Day: Longest Word With All Prefixes
Problem Statement
Problem of The Day: My Calendar I
Problem Statement
Problem of The Day: Sum of Prefix Scores of Strings
Problem Statement
Problem of The Day: Find Peak Element
Problem Statement
Problem of The Day: Largest Number
Problem Statement
Problem of The Day: Uncommon Words from Two Sentences
Problem Statement
Problem of The Day: Minimum Time Difference
Problem Statement
Problem of The Day: Smallest Common Region
Problem Statement
Problem of The Day: Longest Subarray With Maximum Bitwise AND
Problem Statement
Problem of The Day: Count the Number of Consistent Strings
Problem Statement
Problem of The Day: Count the Number of Consistent Strings
Problem Statement
Problem of The Day: Basic Calculator II
Problem Statement
Problem of The Day: Minimum Bit Flips to Convert Number
Problem Statement
Problem of The Day: Pow(x, n)
Problem Statement
Problem of The Day: Insert Greatest Common Divisors in Linked List
Problem Statement
Problem of The Day: K Closest Points to Origin
Problem Statement
Problem of The Day: Split Linked List in Parts
Problem Statement
Problem of The Day: Valid Word Abbreviation
Problem Statement
Problem of The Day: Spiral Matrix IV
Problem Statement
Problem of The Day: Lowest Common Ancestor of a Binary Tree III
Problem Statement
Problem of The Day: Dot Product of Two Sparse Vectors
Problem Statement
Problem of The Day: Meeting Scheduler
Problem Statement
Problem of The Day: Nested List Weight Sum
Problem Statement
Problem of The Day: Binary Tree Vertical Order Traversal
Problem Statement
Problem of The Day: Word Search II
Problem Statement
Problem of The Day: Linked List in Binary Tree
Problem Statement
Problem of The Day: Delete Nodes From Linked List Present in Array
Problem Statement
Windows Task Scheduler
Sometimes, we need to run daily task or schedule a process to run on a window server. This can be tedious and time consuming. So, it’s better to find a way t...
Problem of The Day: Sum of Digits of String After Convert
Problem Statement
Problem of The Day: Find the Student that Will Replace the Chalk
Problem Statement
Problem of The Day: Convert 1D Array Into 2D Array
Problem Statement
Problem of The Day: Path with Maximum Probability
Problem Statement
Design Pattern: Prototype
Motivation
Problem of The Day: Most Stones Removed with Same Row or Column
Problem Statement
Problem of The Day: Count Sub Islands
Problem Statement
Problem of The Day: Path with Maximum Probability
Problem Statement
Problem of The Day: Path with Maximum Probability
Problem Statement
Problem of The Day: Range Sum of Sorted Subarray Sums
Problem Statement
Problem of The Day: N-ary Tree Postorder Traversal
Problem Statement
Problem of The Day: Find the Closest Palindrome
Problem Statement
Problem of The Day: Fraction Addition and Subtraction
Problem Statement
Azure DevOps: Azure-pipeline templates
In the past, we explored how to create a simple CI/CD pipeline. Then, we went through the steps to create a CI/CD pipeline for multiple release sites. In thi...
Problem of The Day: Maximum Distance in Arrays
Problem Statement
Azure DevOps: CICD Multiple Release Pipelines
In this journal, we will take another step after setting up the CICD pipeline in previous Journal.
Problem of The Day: Lemonade Change
Problem Statement
Problem of The Day: Find K-th Smallest Pair Distance
Problem Statement
Azure Devops: CICD Setup
In this tutorial, we will explore how to create CICD pipeline on the Azure Devops environment.
Problem of The Day: Combination Sum II
Problem Statement
Problem of The Day: Regions Cut By Slashes
Problem Statement
Problem of The Day: Magic Squares In Grid
Problem Statement
Situation Validation in C#
Introduction
Problem of The Day: Spiral Matrix III
Problem Statement
Problem of The Day: Integer to English Words
Problem Statement
Design Pattern: Factories
Motivation
The SOLID Design Principles Review
SOLID Principles Summary
Problem of The Day: Minimum Number of Pushes to Type Word II
Problem Statement
Problem of The Day: Kth Distinct String in an Array
Problem Statement
Problem of The Day: Minimum Deletions to Make String Balanced
Problem Statement
Problem of The Day: Count Number of Teams
Problem Statement
Problem of The Day: Minimum Cost to Convert String I
Problem Statement
Problem of The Day: Find the City With the Smallest Number of Neighbors at a Threshold Distance
Problem Statement
Problem of The Day: Sort an Array
Problem Statement
Problem of The Day: Sort the Jumbled Numbers
Problem Statement
Problem of The Day: Sort Array by Increasing Frequency
Problem Statement
Problem of The Day: Build a Matrix With Conditions
Problem Statement
Problem of The Day: Find Distance in a Binary Tree
Problem Statement
Problem of The Day: Lucky Numbers in a Matrix
Problem Statement
Problem of The Day: Delete Nodes And Return Forest
Problem Statement
Problem of The Day: Number of Atoms
Problem Statement
Problem of The Day: Create Binary Tree From Descriptions
Problem Statement
Problem of The Day: Robot Collisions
Problem Statement
Problem of The Day: Maximum Score From Removing Substrings
Problem Statement
Problem of The Day: Reverse Substrings Between Each Pair of Parentheses
Problem Statement
Problem of The Day: Average Waiting Time
Problem Statement
Problem of The Day: Find the Winner of the Circular Game
Problem Statement
Problem of The Day: Pass the Pillow
Problem Statement
Problem of The Day: Water Bottles
Problem Statement
Problem of The Day: Merge Nodes in Between Zeros
Problem Statement
Problem of The Day: Find the Minimum and Maximum Number of Nodes Between Critical Points
Problem Statement
Problem of The Day: Three Consecutive Odds
Problem Statement
Problem of The Day: All Ancestors of a Node in a Directed Acyclic Graph
Problem Statement
Problem of The Day: Maximum Total Importance of Roads
Problem Statement
Problem of The Day: Minimum Number of K Consecutive Bit Flips
Problem Statement
Problem of The Day: Balance a Binary Search Tree
Problem Statement
Problem of The Day: Binary Search Tree to Greater Sum Tree
Problem Statement
Problem of The Day: Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit
Problem Statement
Problem of The Day: Grumpy Bookstore Owner
Problem Statement
Problem of The Day: Most Profit Assigning Work
Problem Statement
Problem of The Day: Sum of Square Numbers
Problem Statement
Problem of The Day: IPO
Problem Statement
Problem of The Day: Sort Colors
Problem Statement
Problem of The Day: Subarray Sums Divisible by K
Problem Statement
Problem of The Day: Replace Words
Problem Statement
Problem of The Day: Hand of Straights
Problem Statement
Problem of The Day: Find Common Characters
Problem Statement
Problem of The Day: Append Characters to String to Make Subsequence
Problem Statement
Problem of The Day: Number of Steps to Reduce a Number in Binary Representation to One
Problem Statement
Problem of The Day: Get Equal Substrings Within Budget
Problem Statement
Problem of The Day: Student Attendance Record II
Problem Statement
Problem of The Day: Word Break II
Problem Statement
Problem of The Day: Maximum Score Words Formed by Letters
Problem Statement
Problem of The Day: Sum of All Subset XOR Totals
Problem Statement
Problem of The Day: Delete Leaves With a Given Value
Problem Statement
Problem of The Day: Path with Maximum Gold
Problem Statement
Problem of The Day: Score After Flipping Matrix
Problem Statement
Problem of The Day: Minimum Cost to Buy Apples
Problem Statement
Problem of The Day: Largest Local Values in a Matrix
Problem Statement
Problem of The Day: K-th Smallest Prime Fraction
Problem Statement
Problem of The Day: Maximize Happiness of Selected Children
Problem Statement
Problem of The Day: Double a Number Represented as a Linked List
Problem Statement
Problem of The Day: Remove Nodes From Linked List
Problem Statement
Problem of The Day: Delete Node in a Linked List
Problem Statement
Problem of The Day: Boats to Save People
Problem Statement
Problem of The Day: Count Pairs in Two Arrays
Problem Statement
Problem of The Day: Compare Version Numbers
Problem Statement
Problem of The Day: Word Search
Problem Statement
Problem of The Day: Construct Quad Tree
Problem Statement
Problem of The Day: Generate Parentheses
Problem Statement
Problem of The Day: Sort List
Problem Statement
Problem of The Day: Sum of Distances in Tree
Problem Statement
Problem of The Day: Number of Islands II
Problem Statement
Problem of The Day: Freedom Trail
Problem Statement
Problem of The Day: Minimum Falling Path Sum II
Problem Statement
Problem of The Day: Longest Ideal Subsequence
Problem Statement
Problem of The Day: Minimum Height Trees
Problem Statement
Problem of The Day: Open the Lock
Problem Statement
Problem of The Day: Design Add and Search Words Data Structure
Problem Statement
Problem of The Day: Find if Path Exists in Graph
Problem Statement
Problem of The Day: Find All Groups of Farmland
Problem Statement
Problem of The Day: Island Perimeter
Problem Statement
Problem of The Day: Smallest String Starting From Leaf
Problem Statement
Problem of The Day: Sum of Left Leaves
Intuition
Problem of The Day: Remove K Digits
Problem Statement
Problem of The Day: Reveal Cards In Increasing Order
Problem Statement
Problem of The Day: Construct String from Binary Tree
Problem Statement
Problem of The Day: Time Needed to Buy Tickets
Problem Statement
Problem of The Day: Time Needed to Buy Tickets
Problem Statement
Problem of The Day: Number of Students Unable to Eat Lunch
Problem Statement
Problem of The Day: Valid Parenthesis String
Problem Statement
Problem of The Day: minimum-remove-to-make-valid-parentheses
Problem Statement
Problem of The Day: Length of Longest Subarray With at Most K Frequency
Problem Statement
Problem of The Day: Subarray Product Less Than K
Problem Statement
Daily Reading: The Art of Thinking Clearly (day 7)
Today’s Vocabulary
Problem of The Day: Count and Say
Problem Statement
Problem of The Day: Snakes and Ladders
Problem Statement
Problem of The Day: Find All Duplicates in an Array
Problem Statement
Problem of The Day:Minimum Genetic Mutation
Problem Statement
Problem of The Day: Find the Duplicate Number
Problem Statement
Problem of The Day: Evaluate Division
Problem Statement
Problem of The Day: Reorder List
Problem Statement
Problem of The Day: Clone Graph
Problem Statement
Problem of The Day: Remove Vowels from a String
Problem Statement
Daily Reading: The Art of Thinking Clearly (day 6)
Today’s Vocabulary
Daily Reading: The Art of Thinking Clearly (day 5)
Today’s Vocabulary
Problem of The Day: Contiguous Array
Problem Statement
Problem of The Day: Palindrome Linked List
Problem Statement
Problem of The Day: Surrounded Regions
Problem Statement
Problem of The Day: Minimum Time to Make Rope Colorful
Problem Statement
Problem of The Day: Merge In Between Linked Lists
Problem Statement
Problem of The Day: Minimum Absolute Difference in BST
Problem Statement
Problem of The Day: Binary Search Tree Iterator
Problem Statement
Problem of The Day: Contiguous Array
Problem Statement
Problem of The Day: Binary Tree Maximum Path Sum
Problem Statement
Problem of The Day: Average of Levels in Binary Tree
Problem Statement
Daily Reading: On Writing Well (Chapter 5)
Today’s Vocabulary
Problem of The Day: Meeting Room II
Problem Statement
Problem of The Day: Count Complete Tree Nodes
Problem Statement
Problem of The Day: Sum Root to Leaf Numbers
Problem Statement
Daily Reading: The Art of Thinking Clearly (day 4)
Today’s Vocabulary
Problem of The Day: Path Sum
Problem Statement
Problem of The Day: Populating Next Right Pointers in Each Node II
Problem Statement
Problem of The Day: Binary Subarrays With Sum
Problem Statement
Daily Reading: On Writing Well (Chapter 4)
Today’s Vocabulary
Daily Reading: The Art of Thinking Clearly (day 3)
Today’s Vocabulary
Problem of The Day: Find the Pivot Integer
Problem Statement
Problem of The Day: Rotate List
Problem Statement
Daily Reading: The Art of Thinking Clearly (day 2)
Today’s Vocabulary
Problem of The Day: Custom Sort String
Problem Statement
Problem of The Day: Linked List Frequency
Problem Statement
Problem of The Day: Remove Zero Sum Consecutive Nodes from Linked List
Problem Statement
Problem of The Day: Winner of the Linked List Game
Problem Statement
Problem of The Day: Intersection of Two Arrays
Problem Statement
Problem of The Day: Add Binary
Problem Statement
Problem of The Day: Valid Palindrome II
Problem Statement
Problem of The Day: Valid Word Abbreviation
Problem Statement
Problem of The Day: Minimum Common Value
Problem Statement
SQL problem - Rank Scores
Problem
Problem of The Day: Partition List
Problem Statement
Problem of The Day: Fizz Buzz
Problem Statement
Problem of The Day: Reverse Nodes in k-Group
Problem Statement
Problem of The Day: Remove Duplicates from Sorted List II
Problem Statement
Problem of The Day: Count Elements With Maximum Frequency
Problem Statement
Problem of The Day: Basic Calculator
Problem Statement
Problem of The Day: Reverse Linked List II
Problem Statement
Reading Exercise: The Art of Thinking Clearly (day 1)
Today’s Vocabulary
Problem of The Day: Minimum Length of String After Deleting Similar Ends
Problem Statement
Problem of The Day: Bag of Tokens
Problem Statement
SQL problem - Restaurant Growth
Problem
Problem of The Day: Remove Nth Node From End of List
Problem Statement
SQL problem - Movie Rating
Problem
Problem of The Day: Simplify Path
Problem Statement
Problem of The Day: Squares of a Sorted Array
Problem Statement
SQL problem - Exchange Seats
Problem
Problem of The Day: Min Stack
Problem Statement
Problem of The Day: Minimum Number of Arrows to Burst Balloons
Problem Statement
Daily Reading: System Design Interview Volume 2 (finished)
Update my reading list
Problem of The Day: Maximum Odd Binary Number
Problem Statement
Problem of The Day: Insert Interval
Problem Statement
Problem of The Day: Paint Fence
Problem Statement
Problem of The Day: Flip Game
Problem Statement
Problem of The Day: Even Odd Tree
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 16)
Today’s Vocabulary
Problem of The Day: Diameter of Binary Tree
Problem Statement
Problem of The Day: Happy Number
Problem Statement
Problem of The Day: Diameter of Binary Tree
Problem Statement
Problem of The Day: Same Tree
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 15)
Today’s Vocabulary
Problem of The Day: Happy Number
Problem Statement
Problem of The Day: Contains Duplicate II
Problem Statement
SQL problem - Triangle Judgement
Problem
Problem of The Day: Greatest Common Divisor Traversal
Problem Statement
Problem of The Day: Find All People With Secret
Problem Statement
Problem of The Day: Word Pattern
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 14)
Today’s Vocabulary
Problem of The Day: Cheapest Flights Within K Stops
Problem Statement
Problem of The Day: Valid Sudoku
Problem Statement
Problem of The Day: Spiral Matrix
Problem Statement
Problem of The Day: Isomorphic Strings
Problem Statement
Problem of The Day: Game of Life
Problem Statement
Problem of The Day: Find the Town Judge
Problem Statement
Problem of The Day: Substring with Concatenation of All Words
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 13)
Today’s Vocabulary
Problem of The Day: Ransom Note
Problem Statement
C# ASP.NET - Add Foreign Key In Entity Framework
How to add relationship in EFCore
Problem of The Day: Bitwise AND of Numbers Range
Problem Statement
Problem of The Day: Missing Number
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 12)
Today’s Vocabulary
Problem of The Day: Power of Two
Problem Statement
Problem of The Day: Two Sum II - Input Array Is Sorted
Problem Statement
Problem of The Day: Minimum Size Subarray Sum
Problem Statement
Problem of The Day: Meeting Rooms III
Problem Statement
Problem of The Day: Furthest Building You Can Reach
Problem Statement
Problem of The Day: Text Justification
Problem Statement
Problem of The Day: Is Subsequence
Problem Statement
Problem of The Day: Find Polygon With the Largest Perimeter
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 11)
Today’s Vocabulary
Problem of The Day: Find Polygon With the Largest Perimeter
Problem Statement
Problem of The Day: Rearrange Array Elements by Sign
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 10)
Today’s Vocabulary
Problem of The Day: Integer to Roman
Problem Statement
Problem of The Day: Zigzag Conversion
Problem Statement
Review Repository Pattern in ASP.NET
The code is pushed to this GitHub repo.
Daily Reading: The 7 Habits of Highly Effective People (day 9)
Today’s Vocabulary
Problem of The Day: Find First Palindromic String in the Array
Problem Statement
C# .NET - Entity Framework notes
AsNoTracking
Problem of The Day: Trapping Rain Water
Problem Statement
Problem of The Day: Reverse Words in a String
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 8)
My Person Mission Statement
SQL problem - Confirmation Rate
Problem
Problem of The Day: Cherry Pickup II
Problem Statement
Problem of The Day: Candy
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 7)
Today’s Vocabulary
Problem of The Day: Palindromic Substrings
Problem Statement
SQL problem - Not Boring Movies
Problem
Problem of The Day: Longest Common Prefix
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 6)
Today’s Vocabulary
Problem of The Day: Largest Divisible Subset
Problem Statement
.NET C# - Entity Framework Core Review Note
What is Entity Framework Core (ORM)
Daily Reading: The 7 Habits of Highly Effective People (day 5)
Today’s Vocabulary
.NET C# - RESTful Web API Note (continue)
The code is pushed to this GitHub repo.
Problem of The Day: Perfect Squares
Problem Statement
How to consume API and review JavaScript
The purpose of this journal is to review and practice how to make API calls in javascript via a simple REST API endpoints. This is the practice that I do in ...
Problem of The Day: Sort Characters By Frequency
Problem Statement
Problem of The Day: Roman to Integer
Problem Statement
SQL problem - Rising Temperature
Problem
Daily Reading: The 7 Habits of Highly Effective People (day 4)
Today’s Vocabulary
.NET C# - RESTful Web API Note
The Request Object
SQL problem - Employee Bonus
Problem
Daily Reading: The 7 Habits of Highly Effective People (day 3)
Today’s Vocabulary
Problem of The Day: H-Index
Problem Statement
Problem of The Day: Group Anagrams
Problem Statement
Problem of The Day: Gas Station
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People (day 2)
Today’s Vocabulary
Problem of The Day: First Unique Character in a String
Problem Statement
Daily Reading: The 7 Habits of Highly Effective People
Today’s Vocabulary
Problem: Minimum Window Substring
Problem Statement
Problem: Best Time to Buy and Sell Stock II
Problem Statement
SQL problem - Top Travellers
Problem
SQL Review - Part 9
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
SQL problem - Sales Person
Problem
Problem of The Day: Partition Array for Maximum Sum
Problem Statement
SQL problem - Market Analysis I
Problem
SQL problem - Duplicate Emails
Problem
SQL problem - Combine Two Tables
Problem
SQL Review - Part 8
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
SQL Review - Part 7
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
SQL Review - Part 6
In this post, we learn how to use SQL to work with JSON data inside the table.
SQL problem - Swap Salary
Problem
SQL problem - Article Views I
Problem
Problem of The Day: Sequential Digits
Problem Statement
Problem: Remove Duplicates from Sorted Array II
Problem Statement ``` Given an integer array nums sorted in non-decreasing order, remove some duplicates in-place such that each unique element appears at mo...
Problem of The Day: Divide Array Into Arrays With Max Difference
Problem Statement
Problem of The Day: Sort Colors
Problem Statement ``` Given an array nums with n objects colored red, white, or blue, sort them in-place so that objects of the same color are adjacent, with...
Problem of The Day: Next Permutation
Problem Statement ``` A permutation of an array of integers is an arrangement of its members into a sequence or linear order.
Problem of The Day: First Missing Positive
Problem Statement ``` Given an unsorted integer array nums, return the smallest missing positive integer.
Problem of The Day: Find the Index of the First Occurrence in a String
Problem Statement ``` Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of h...
Problem of The Day: Find the Duplicate Number
Problem Statement ``` Given an array of integers nums containing n + 1 integers where each integer is in the range [1, n] inclusive.
Problem of The Day: Evaluate Reverse Polish Notation
Problem Statement see problem
Problem of The Day: Single Number
Problem Statement ``` Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.
Problem of The Day: Rotate Array
Problem Statement ``` Given an integer array nums, rotate the array to the right by k steps, where k is non-negative.
Daily Reading Exercise: Mindset
Today Vocabulary valiant brave Valiant students always strive for success in their studies. pampered spoil The...
Problem of The Day: Product of Array Except Self
Problem Statement ``` Given an integer array nums, return an array answer such that answer[i] is equal to the product of all the elements of nums except nums...
Problem of The Day: Number of Submatrices That Sum to Target
Problem Statement see problem
Problem of The Day: Merge Intervals
Problem Statement ``` Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overla...
Problem of The Day: Maximum Subarray
Problem Statement ``` Given an integer array nums, find the subarray with the largest sum, and return its sum.
Problem of The Day: Majority Element
Problem Statement ``` Given an array nums of size n, return the majority element.
Problem of The Day: Implement Trie (Prefix Tree)
Problem Statement see problem
Problem of The Day: Implement Queue using Stacks
Problem Statement see problem
Problem of The Day: Trapping Rain Water
Problem Statement
Problem of The Day: 3Sum
Problem Statement ``` Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nu...
Problem of The Day: Move Zeroes
Problem Statement ``` Given an integer array nums, move all 0’s to the end of it while maintaining the relative order of the non-zero elements.
Problem of The Day: Container With Most Water
Problem Statement see Problem
Problem of The Day: Valid Parentheses
Problem Statement
Problem of The Day: Min Stack
Problem Statement
Problem of The Day: Largest Rectangle in Histogram
Problem Statement see problem
Problem of The Day: K Inverse Pairs Array
Problem Statement
Problem of The Day: Decode String
Problem Statement
Problem of The Day: Daily Temperatures
Problem Statement
Problem of The Day: Sliding Window Maximum
Problem Statement
Daily Reading Exercise: Mindset
My take on the reading Today, I delved further into Carol S. Dweck’s “Mindset” book, focusing on a chapter that resonated with me about the learnability of a...
Problem of The Day: Out of Boundary Paths
Problem Statement see problem
Problem of The Day: Minimum Window Substring
Problem Statement ``` Given two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in t (i...
SQL Review - Part 5
Tonight, I encountered a SQL question, and through this experience, I discovered the existence of the conditional function IF in SQL. This function allows pe...
Problem of The Day: Spiral Matrix
Problem Statement see problem
Problem of The Day: Set Matrix Zeroes
Problem Statement see problem
Problem of The Day: Search a 2D Matrix II
Problem Statement see problem
Problem of The Day: Rotate Image
Problem Statement see Rotate Image
Problem of The Day: Repeated DNA Sequences
Problem Statement ``` The DNA sequence is composed of a series of nucleotides abbreviated as ‘A’, ‘C’, ‘G’, and ‘T’.
Problem of The Day: Longest Substring Without Repeating Characters
Problem Statement ``` Given a string s, find the length of the longest substring without repeating characters.
Problem of The Day: Find All Anagrams in a String
Problem Statement ``` Given two strings s and p, return an array of all the start indices of p’s anagrams in s. You may return the answer in any order.
Problem of The Day: Longest Common Subsequence
Problem Statement ``` Given two strings text1 and text2, return the length of their longest common subsequence. If there is no common subsequence, return 0.
Code Templates For Technical Interview
In this journal, I aim to compile code templates as a foundational resource to ready myself for technical interviews. These templates are sourced from the Le...
Problem of The Day: Reverse Nodes in k-Group
Problem Statement see problem
Problem of The Day: Pseudo-Palindromic Paths in a Binary Tree
Problem Statement see Pseudo-Palindromic Paths in a Binary Tree
Problem of The Day: Merge k Sorted Lists
Problem Statement ``` You are given an array of k linked-lists lists, each linked-list is sorted in ascending order.
Daily Reading: Mindset
My Daily Reading Today, I learned about the truth of ability and accomplishment. It takes a significant amount of time and effort to develop one’s skills. Ma...
Problem of The Day: Sum of Subarray Minimums
Problem Statement ``` Given an array of integers arr, find the sum of min(b), where b ranges over every (contiguous) subarray of arr. Since the answer may be...
Daily Reading: Mindset
My Daily Reading From tonight’s reading, I’ve learned that our mindset can affect how we see effort. In a fixed mindset, we might look down on people who spe...
Problem of The Day: Maximum Length of a Concatenated String with Unique Characters
Problem Statement ``` You are given an array of strings arr. A string s is formed by the concatenation of a subsequence of arr that has unique characters.
Problem of The Day: LRU Cache
Problem Statement ``` Design a data structure that follows the constraints of a Least Recently Used (LRU) cache.
Problem of The Day: Set Mismatch
Problem Statement ``` You have a set of integers s, which originally contains all the numbers from 1 to n. Unfortunately, due to some error, one of the numbe...
Problem of The Day: Redistribute Characters to Make All Strings Equal
Problem Statement ``` You are given an array of strings words (0-indexed).
Problem of The Day: Largest Substring Between Two Equal Characters
Problem Statement ``` Given a string s, return the length of the longest substring between two equal characters, excluding the two characters. If there is no...
Problem of The Day: Swap Nodes in Pairs
Problem Statement see Swap Nodes in Pairs
Problem of The Day: Sort List
Problem Statement see Sort List
Problem of The Day: Remove Nth Node From End of List
Problem Statement see Remove Nth Node From End of List
Problem of The Day: Palindrome Linked List
Problem Statement see 234. Palindrome Linked List
Problem of The Day: Minimum Falling Path Sum
Problem Statement ``` Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.
Problem of The Day: Linked List Cycle
Problem Statement see Linked List Cycle
Problem of The Day: Linked List Cycle II
Problem Statement see Linked List Cycle II
Problem of The Day: Intersection of Two Linked Lists
Problem Statement see Intersection of Two Linked Lists
Problem of The Day: Copy List with Random Pointer
Problem Statement see Copy List with Random Pointer
Problem of The Day: Add Two Numbers
Problem Statement see Add Two Numbers
Problem of The Day: Reverse Linked List
Problem Statement
Mindset: The New Psychology of Success - Vocabulary
Today, I dedicated an hour to reading “Mindset: The New Psychology of Success” by Carol S. Dweck. In essence, the author elucidates the distinction between a...
Problem of The Day: Merge Two Sorted Lists
Problem Statement ``` You are given the heads of two sorted linked lists list1 and list2.
Problem of The Day: Find Median from Data Stream
Problem Statement ``` The median is the middle value in an ordered integer list. If the size of the list is even, there is no middle value, and the median is...
Problem of The Day: Two Sum
Problem Statement ``` Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target.
Problem of The Day: Top K Frequent Elements
Problem Statement ``` Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.
Problem of The Day: Subarray Sum Equals K
Problem Statement ``` Given an array of integers nums and an integer k, return the total number of subarrays whose sum equals to k.
Problem of The Day: Partition Labels
Problem Statement ``` You are given a string s. We want to partition the string into as many parts as possible so that each letter appears in at most one par...
Problem of The Day: Longest Consecutive Sequence
Problem Statement ``` Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.
Problem of The Day: Kth Largest Element In An Array
Problem Statement ``` Given an integer array nums and an integer k, return the kth largest element in the array.
Problem of The Day: Group Anagrams
Problem Statement ``` Given an array of strings strs, group the anagrams together. You can return the answer in any order.
Problem of The Day: Climbing Stairs
Problem Statement 70. Climbing Stairs
Problem of The Day: Unique Number of Occurrences
Problem Statement ``` Given an array of integers arr, return true if the number of occurrences of each value in the array is unique or false otherwise.
Typescript Basic Learning
In this journal, I wanted to grasp a quick overview about the understanding of Typescript to support my Angular learning.
My Reading Journey
Introduction
Problem of The Day: Jump Game
Problem Statement ``` You are given an integer array nums. You are initially positioned at the array’s first index, and each element in the array represents ...
Problem of The Day: Best Time to Buy and Sell Stock
Problem Statement ``` You are given an array prices where prices[i] is the price of a given stock on the ith day.
Angular Learning - Day 2
Installing Angular CLI This CLI requires nodejs, so we need to install the nodejs first before running following command. npm install -g @angular/cli --no-st...
Problem of The Day: Jump Game II
Problem Statement ``` You are given a 0-indexed array of integers nums of length n. You are initially positioned at nums[0].
Problem of The Day: Rotting Oranges
Problem Statement ``` You are given an m x n grid where each cell can have one of three values:
Problem of The Day: Number of Islands
Problem Statement ``` Given an m x n 2D binary grid grid which represents a map of ‘1’s (land) and ‘0’s (water), return the number of islands.
Problem of The Day: Insert Delete GetRandom O(1)
Problem Statement ``` Implement the RandomizedSet class:
Problem of The Day: Course Schedule
Problem Statement ``` There are a total of numCourses courses you have to take, labeled from 0 to numCourses - 1. You are given an array prerequisites where ...
Angular Learning - Day 1
In this journal, I outline what I have learned about Angular today. I am using this video from FreeCodeCamp as a guideline to help my learning about Angular.
Problem of The Day: Longest Common Subsequence
Problem Statement ``` Given two strings text1 and text2, return the length of their longest common subsequence. If there is no common subsequence, return 0.
Problem of The Day: Find Players With Zero or One Losses
Problem Statement ``` You are given an integer array matches where matches[i] = [winneri, loseri] indicates that the player winneri defeated player loseri in...
Problem of The Day: Partition Equal Subset Sum
Problem Statement ``` Given an integer array nums, return true if you can partition the array into two subsets such that the sum of the elements in both subs...
Problem of The Day: Longest Increasing Subsequence
Problem Statement ``` Given an integer array nums, return the length of the longest strictly increasing subsequence.
Problem of The Day: Determine if Two Strings Are Close
Problem Statement
Problem of The Day: Perfect Square
Problem Statement ``` Given an integer n, return the least number of perfect square numbers that sum to n.
Problem of The Day: Minimum Number of Steps to Make Two Strings Anagram
Problem Statement ``` You are given two strings of the same length s and t. In one step you can choose any character of t and replace it with another charact...
Problem of The Day: Coin Change
Problem Statement ``` You are given an integer array coins representing coins of different denominations and an integer amount representing a total amount of...
Problem of The Day: Maximum Product Subarray
Problem Statement ``` Given an integer array nums, find a subarray that has the largest product, and return the product.
Problem of The Day: Maximum Difference Between Node and Ancestor
Brute Force Problem Statement
Problem of The Day: House Robber
Problem Statement ``` You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constra...
Problem of The Day: Determine if String Halves Are Alike
Problem Statement
Problem of The Day: Word Break
Problem Statement ``` Given a string s and a dictionary of strings wordDict, return true if s can be segmented into a space-separated sequence of one or more...
Problem of The Day: Unique Paths
See problem description here.
Problem of The Day: Minimum Path Sum
Problem Statement
Problem of The Day: Edit Distance
Problem Statement ``` Given two strings word1 and word2, return the minimum number of operations required to convert word1 to word2.
Problem of The Day: Amount of Time for Binary Tree to Be Infected
Problem statement
Problem of The Day: Pascal’s Triangle
Problem Statement
Problem of The Day: Longest Valid Parentheses
Problem Statement
Problem of The Day: Longest Palindromic Substring
Problem Statement ``` Given a string s, return the longest palindromic substring in s.
Problem of The Day: Leaf-Similar Trees
See Problem here.
Problem of The Day: Climbing Stairs
Problem Statement ``` You are climbing a staircase. It takes n steps to reach the top.
Cheatsheet: Flow Chart
In this journal, I’ve documented key insights gathered from the LeetCode platform, which has proven to be both fascinating and invaluable for my interview pr...
Problem of The Day: Range Sum of BST
Problem Statement See problem here.
Problem of The Day: Binary Tree Maximum Path Sum
Problem Statement
Problem of The Day: Arithmetic Slices II - Subsequence
Problem Statement ``` Given an integer array nums, return the number of all the arithmetic subsequences of nums.
Problem of The Day: Maximum Profit in Job Scheduling
Problem Statement
Problem of The Day: Lowest Common Ancestor of a Binary Tree
Problem Statement
Problem of The Day: Kth Smallest Element in a BST
Problem Statement
SQL Review - Part 4
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
Problem of The Day: Path Sum III
Problem Statement Intuition The problem requires finding the number of paths in a binary tree where the sum of node values along the path equals a given tar...
Problem of The Day: Longest Increasing Subsequence
Problem Statement Intuition When approaching the problem of finding the length of the Longest Increasing Subsequence (LIS), my initial thoughts revolved aro...
Problem of The Day: Flatten Binary Tree to Linked List
Problem Statement Intuition My initial thought to solve this problem is to perform a recursive depth-first traversal of the binary tree. I want to flatten t...
SQL Review - Part 3
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
SQL Review - Part 2
In this post, I continue the review of my knowledge about SQL. The materials are from the Leet Code SQL card
SQL Review - Part 1
In this post, I wanted to review my basic knowledge about SQL. The materials are from the Leet Code SQL card
Problem of The Day: Minimum Number of Operations to Make Array Empty
Problem Statement ``` You are given a 0-indexed array nums consisting of positive integers.
Problem of The Day: Invert Binary Tree
Problem Statement
Problem: Diameter of Binary Tree
Problem Statement Intuition The problem aims to find the diameter of a binary tree, which is the length of the longest path between any two nodes in a tree....
Problem of The Day: Convert Sorted Array to Binary Search Tree
Problem Statement Given an integer array nums where the elements are sorted in ascending order, convert it to a height-balanced binary search tree.
Problem: Binary Tree Right Side View
Problem Statement Intuition The problem suggests finding the right side view of a binary tree, indicating a level-order traversal (BFS) approach. My initial...
Problem of The Day: Number of Laser Beams in a Bank
Problem Statement ``` Anti-theft security devices are activated inside a bank. You are given a 0-indexed binary string array bank representing the floor plan...
Problem of The Day: Convert an Array Into a 2D Array With Conditions
Problem Statement ``` You are given an integer array nums. You need to create a 2D array from nums satisfying the following conditions:
Problem of The Day: Construct Binary Tree from Preorder and Inorder Traversal
Problem Statement ``` Given two integer arrays preorder and inorder where preorder is the preorder traversal of a binary tree and inorder is the inorder trav...
Problem of The Day: Assign Cookies
Problem Statement ``` Assume you are an awesome parent and want to give your children some cookies. But, you should give each child at most one cookie.
Problem of The Day: Validate Binary Search Tree
Problem Statement See link
Problem of The Day: Median of Two Sorted Arrays
Today, I tackled a challenging problem from the Top 100 Liked Problem List. It proved to be quite difficult, and despite my best efforts, I couldn’t arrive a...
Problem of The Day: Binary Tree Level Order Traversal
Problem Statement See the link
Problem of The Day: Symmetric Tree
Problem Statement ``` Given the root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center).
Problem of The Day: Binary Tree Inorder Traversal
Problem Statement ``` Given the root of a binary tree, return the inorder traversal of its nodes’ values.
2023
Problem of The Day: Search a 2D Matrix
Problem Statement
Problem of The Day: Maximum Average Subtree
Problem Statement
Problem of The Day: Find First And Last Position of Element In Sorted Array
Problem Statement ``` Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value.
Problem of The Day: Search In Rotated Sorted Array
Today, my primary focus was on honing my skills in Binary Search, and I decided to tackle the problem known as “Search in Rotated Sorted Array.” Despite maki...
Problem of The Day: Find Minimum in Rotated Sorted Array
Problem Statement Here is the description for this problem.
Problem of The Day: Word Search
Today, I tackled the Word Search problem within the backtrack section of the Top 100 Liked on LeetCode. After engaging with several backtrack problems, I gai...
Problem of The Day: Search Insert Position
Problem Statement In this post, I aim to delve into an important topic for preparing technical interviews – Binary Search. The crux of Binary Search lies in ...
Problem of The Day: Palindrome Partitioning
Problem Statement This problem represents the final challenge within the Backtracking category among my Top 100 Liked problems. The objective is to generate ...
Problem of The Day: N-Queens
Today, I continued my exploration of the Top 100 Liked List on LeetCode, where I encountered another challenging problem related to the Backtracking topic - ...
Problem of The Day: Subsets
Similar to the Permutations problem on my other post, this problem involved in the backtrack topic. The interesting thing about this problem is that there ar...
Problem of The Day: Permutations
Tonight, I delved into the Top 100 Liked List, continuing my exploration of the Backtracking topic. The focal point of today’s study is a classic problem kno...
Embracing Setbacks: Learning from Failure
Facing the IBM Assessment Challenge Today marked another attempt at the IBM Frontend role coding assessment, and it didn’t go as expected. The complexity of ...
Problem of The Day: Combination Sum
Today, I continue practicing solving Leet Code problems. I tackle the Top 100 Liked on the Backtracking topic again. Problem of The Day is called Combination...
Stabilize the CodeTrack Project
Figure out how to set up Azure Key Vault Today, I dedicated the entire morning to configuring Azure Key Vault for my CodeTrack application, aiming to securel...
In-Depth questions for C#
What are managed and unmanaged pieces of code? Managed and unmanaged code refer to how programming code is handled in terms of memory management and executio...
Problem of The Day: Generate Parentheses
Today, I took on a more challenging problem within the realm of backtracking.
General C# Knowledge for interview preparation
In this journal, I want to list the general questions about C# knowledge to prepare for technical interviews. Value types vs. reference types Value types ...
Object Oriented Programming interview questions
In this journal, I want to review and layout the common questions for OOP topic in an interview. What is object-oriented programming, and why is it beneficia...
Problem of The Day: Maximum Depth of Binary Tree
Today, I tackled a straightforward LeetCode question. Despite being on the go, I’m committed to daily problem-solving and documenting my explanations for eff...
Crafting a Blueprint for Transformation: My Journey to Becoming the Best Version of Myself
A Blueprint for Growth In this journal, I’m outlining my lifetime goals, covering both short-term and long-term aspirations. My goals have taken a backseat f...
Back To Leetcode Grinding
Restarting the LeetCode Journey Today marks the beginning of my renewed commitment to daily LeetCode practice. I’ve set a goal to solve at least one problem ...
Mastering the Interview Process: Essential Questions and Resources
I’m crafting this post to highlight essential questions crucial for interview preparation.
General Software Engineering Questions
Explain Object-Oriented Programming (OOP) and its principles.
Back in the Leetcode Arena After the CodeTrack Launch — Hardcore Mode Activated
Revised Plan Landing/Home Page on CodeTrack Deployment Project Testing Figure out how to use Azure Key Vault to keep secret Solve Leetcode problem
CodeTrack Development Update - Overcoming Challenges and Progressing Forward
CodeTrack Development Progress
A Week Passed
Personal Project development Today, I dedicated my morning to advancing my CodeTrack project. The notable progress involved the addition of two essential but...
Progress Day
A Positive Start and Professional Development
Challenges and Reflections
Facing Rejections and Demotivation
Productive Day
Morning Hustle: Giving It All for the Personal Project Today marked another chapter in the adventurous coding journey of mine! The day kicked off at a cool 1...
Lazy Sunday Turns Coding Adventure
Lazy Morning Today felt like just another lazy Sunday, where my morning started fashionably late at 11 AM. Lazing around, I got sucked into the vortex of my ...
Reconnect with Friends and Keep Grinding: A Comedy of Code and Coffee
Meeting up with college friend Today’s tale is a rollercoaster of coding, coffee, and an unexpected reunion with the outside world. Buckle up, because we’re ...
Just Another Day in the Unemployment Playground: Adventures of a Software Sorcerer Without a Desk!
Why am I writing? So, here I am, facing the blank digital canvas, wondering what wacky words will dance across the screen today. Frankly, I have no freaking ...
My First Post
The next chapter My life after quitting Siemens as a Software Engineer since September 2023? Honestly, it’s a dumpster fire! Job hunting feels like navigatin...