Learning Journal

A journal of habit-forming shenanigans


LeetCode 75


Array / String
Problem Difficulty Status
Merge Strings Alternately Easy Solved
Greatest Common Divisor of Strings Easy Solved
Kids With the Greatest Number of Candies Easy Solved
Can Place Flowers Easy Solved
Reverse Vowels of a String Easy Solved
Reverse Words in a String Medium Solved
Product of Array Except Self Medium Solved
Increasing Triplet Subsequence Medium Solved
String Compression Medium Solved


Two Pointers
Problem Difficulty Status
Move Zeroes Easy Solved
Is Subsequence Easy Solved
Container With Most Water Medium Solved
Max Number of K-Sum Pairs Medium Solved


Sliding Window
Problem Difficulty Status
Maximum Average Subarray I Easy Solved
Maximum Number of Vowels in a Substring of Given Length Medium Solved
Max Consecutive Ones III Medium Solved
Longest Subarray of 1's After Deleting One Element Medium Solved


Prefix Sum
Problem Difficulty Status
Find the Highest Altitude Easy Solved
Find Pivot Index Easy Solved


Hash Map / Set
Problem Difficulty Status
Find the Difference of Two Arrays Easy Solved
Unique Number of Occurrences Easy Solved
Determine if Two Strings Are Close Medium Solved
Equal Row and Column Pairs Medium Solved


Stack
Problem Difficulty Status
Removing Stars From a String Medium Solved
Asteroid Collision Medium Solved
Decode String Medium Solved


Queue
Problem Difficulty Status
Number of Recent Calls Easy Solved
Dota2 Senate Medium Solved


Linked List
Problem Difficulty Status
Delete the Middle Node of a Linked List Medium
Odd Even Linked List Medium
Reverse Linked List Easy
Maximum Twin Sum of a Linked List Medium


Binary Tree - DFS
Problem Difficulty Status
Maximum Depth of Binary Tree Easy
Leaf-Similar Trees Easy
Count Good Nodes in Binary Tree Medium
Path Sum III Medium
Longest ZigZag Path in a Binary Tree Medium
Lowest Common Ancestor of a Binary Tree Medium


Binary Tree - BFS
Problem Difficulty Status
Binary Tree Right Side View Medium
Maximum Level Sum of a Binary Tree Medium


Binary Search Tree
Problem Difficulty Status
Search in a Binary Search Tree Easy
Delete Node in a BST Medium


Graphs - DFS
Problem Difficulty Status
Keys and Rooms Medium
Number of Provinces Medium
Reorder Routes to Make All Paths Lead to the City Zero Medium
Evaluate Division Medium


Graphs - BFS
Problem Difficulty Status
Nearest Exit from Entrance in Maze Medium
Rotting Oranges Medium


Heap / Priority Queue
Problem Difficulty Status
Kth Largest Element in an Array Medium
Smallest Number in Infinite Set Medium
Maximum Subsequence Score Medium
Total Cost to Hire K Workers Medium


Problem Difficulty Status
Guess Number Higher or Lower Easy
Successful Pairs of Spells and Potions Medium
Find Peak Element Medium
Koko Eating Bananas Medium


Backtracking
Problem Difficulty Status
Letter Combinations of a Phone Number Medium
Combination Sum III Medium


DP - 1D
Problem Difficulty Status
N-th Tribonacci Number Easy
Min Cost Climbing Stairs Easy
House Robber Medium
Domino and Tromino Tiling Medium


DP - Multidimensional
Problem Difficulty Status
Unique Paths Medium
Longest Common Subsequence Medium
Best Time to Buy and Sell Stock with Transaction Fee Medium
Edit Distance Medium


Bit Manipulation
Problem Difficulty Status
Counting Bits Easy
Single Number Easy
Minimum Flips to Make a OR b Equal to c Medium


Trie
Problem Difficulty Status
Implement Trie (Prefix Tree) Medium
Search Suggestions System Medium


Intervals
Problem Difficulty Status
Non-overlapping Intervals Medium
Minimum Number of Arrows to Burst Balloons Medium


Monotonic Stack
Problem Difficulty Status
Daily Temperatures Medium
Online Stock Span Medium