My LeetCode Journey

Solutions organized by the approach used to solve each problem.

Backtracking
40. Combination Sum II
51. N Queens
78. Subsets
90. Subsets II
2044. Count Number of Maximum Bitwise OR Subsets

---

Binary Search
162. Find Peak Element
374. Guess Number Higher or Lower
700. Search in a Binary Search Tree
875. Koko Eating Bananas
2300. Successful Pairs of Spells and Potions
3312. Sorted GCD Pair Queries

---

Bit Manipulation
190. Reverse Bits

---

Block Iteration
3499. Maximize Active Section with Trade I

---

Boolean Array Marking Presence
3718. Smallest Missing Multiple of K

---

Brute Force
1763. Longest Nice Substring
1967. Number of Strings That Appear as Substrings in Word
2373. Largest Local Values in a Matrix
4010. Maximize Pair Strength Using GCD
4011. Count Subarrays With Even Odd Ratio I

---

Counting Frequency And Constructing Palindrome
3517. Smallest Palindromic Rearrangement I

---

Counting Sort
75. Sort Colors

---

Counting Total Equal Adjacent Pairs With A Heuristic Formula
4043. Count Rotations With Exactly K Equal Adjacent Pairs

---

Direct Calculation
3986. Number of Elapsed Seconds Between Two Times

---

Direct Formula Computation With Euclidean GCD
3658. GCD of Odd and Even Sums

---

Divide and Conquer
263. Ugly Number
761. Special Binary String

---

Dynamic Programming
62. Unique Paths
72. Edit Distance
115. Distinct Subsequences
120. Triangle
486. Predict the Winner
509. Fibonacci Number
516. Longest Palindromic Subsequence
746. Min Cost Climbing Stairs
877. Stone Game
940. Distinct Subsequences II
1092. Shortest Common Supersequence
3987. Minimum Total Cost to Process All Elements

---

Factorial Number System With List Removal (direct Construction)
60. Permutation Sequence

---

Greedy
122. Best Time to Buy and Sell Stock II
316. Remove Duplicate Letters
334. Increasing Triplet Subsequence
1081. Smallest Subsequence of Distinct Characters
1328. Break a Palindrome
1488. Avoid Flood in The City
2144. Minimum Cost of Buying Candies With Discount
2335. Minimum Amount of Time to Fill Cups
3014. Minimum Number of Pushes to Type Word I
3016. Minimum Number of Pushes to Type Word II
3974. Maximum Total Sum of K Selected Elements
4014. Minimum Total Price After Applying Discounts

---

Hash Counting
3731. Find Missing Elements

---

Hash Map
347. Top K Frequent Elements
594. Longest Harmonious Subsequence
1207. Unique Number of Occurrences
1394. Find Lucky Integer in an Array
2352. Equal Row and Column Pairs

---

Hash Set
1. Two Sum

---

Hash Set Solution
2357. Make Array Zero by Subtracting Equal Amounts

---

HashSet To Track Unique Characters
3760. Maximum Substrings With Distinct Start

---

Heap / Priority Queue
215. Kth Largest Element in an Array
378. Kth Smallest Element in a Sorted Matrix
506. Relative Ranks
703. Kth Largest Element in a Stream
1337. The K Weakest Rows in a Matrix
2099. Find Subsequence of Length K With the Largest Sum
2231. Largest Number After Digit Swaps by Parity
2336. Smallest Number in Infinite Set

---

Incremental Array Update
66. Plus One

---

Insertion Sort
147. Insertion Sort List

---

Iterate Over Digits To Compute Sum And Product
3622. Check Divisibility by Digit Sum and Product

---

Iterate Through Digits To Find The Two Largest Values
3536. Maximum Product of Two Digits

---

Iterative Linked List Reversal
206. Reverse Linked List

---

Iterative Prefix Validation
4006. Count Valid Prefixes

---

Linear Scan To Locate Min And Max Indices And Compute Minimal Deletions
2091. Removing Minimum and Maximum From Array

---

Linear Scan With Conditional Checks
8. String to Integer atoi

---

Linear Scan With Early Return
3978. Unique Middle Element

---

Linear Scan With Two Dynamic Lists
3069. Distribute Elements Into Two Arrays I

---

Modified Prefix Product Calculation
2906. Construct Product Matrix

---

Prefix And Suffix Product Arrays
238. Product of Array Except Self

---

Prefix Max & Suffix Min Precomputation
3904. Smallest Stable Index II

---

Prefix Sum
303. Range Sum Query Immutable
724. Find Pivot Index
1732. Find the Highest Altitude
1991. Find the Middle Index in Array
2996. Smallest Missing Integer Greater Than Sequential Prefix Sum
3737. Count Subarrays With Majority Element I

---

Recursive BST Delete Using Inorder Successor/predecessor
450. Delete Node in a BST

---

Sequential Digit Generation
1291. Sequential Digits

---

Simple Grid Construction With Obstacles
3963. Create Grid With Exactly One Path

---

Single Pass Scan For Minimum Odd And Even Values
3876. Construct Uniform Parity Array II

---

Single Pass To Find Top 3 Maximums And 2 Minimums
628. Maximum Product of Three Numbers

---

Sliding Window
239. Sliding Window Maximum
643. Maximum Average Subarray I
933. Number of Recent Calls
1004. Max Consecutive Ones III
1358. Number of Substrings Containing All Three Characters
1456. Maximum Number of Vowels in a Substring of Given Length
1493. Longest Subarray of 1s After Deleting One Element
3090. Maximum Length Substring With Two Occurrences
3318. Find X Sum of All K Long Subarrays I
4044. Count Good Cyclic Rotations

---

Sorting
451. Sort Characters By Frequency
2500. Delete Greatest Value in Each Row

---

Stack
84. Largest Rectangle in Histogram

---

String
151. Reverse Words in a String
1071. Greatest Common Divisor of Strings
1668. Maximum Repeating Substring
3612. Process String with Special Operations I

---

Two Pointer
11. Container With Most Water
15. 3Sum
16. 3Sum Closest
18. 4Sum
19. Remove Nth Node From End of List
392. Is Subsequence
977. Squares of a Sorted Array
1768. Merge Strings Alternately
2095. Delete the Middle Node of a Linked List
2130. Maximum Twin Sum of a Linked List

---

Unknown
94. Binary Tree Inorder Traversal
124. Binary Tree Maximum Path Sum
199. Binary Tree Right Side View
264. Ugly Number II
283. Move Zeroes
345. Reverse Vowels of a String
394. Decode String
443. String Compression
547. Number of Provinces
605. Can Place Flowers
649. Dota2 Senate
735. Asteroid Collision
841. Keys and Rooms
872. Leaf Similar Trees
1046. Last Stone Weight
1137. N th Tribonacci Number
1161. Maximum Level Sum of a Binary Tree
1260. Shift 2D Grid
1312. Minimum Insertion Steps to Make a String Palindrome
1372. Longest ZigZag Path in a Binary Tree
1431. Kids With the Greatest Number of Candies
1448. Count Good Nodes in Binary Tree
1464. Maximum Product of Two Elements in an Array
1588. Sum of All Odd Length Subarrays
1679. Max Number of K Sum Pairs
1926. Nearest Exit from Entrance in Maze
1979. Find Greatest Common Divisor of Array
2215. Find the Difference of Two Arrays
2390. Removing Stars From a String
2558. Take Gifts From the Richest Pile
3471. Find the Largest Almost Missing Integer
3514. Number of Unique XOR Triplets II
3568. Minimum Moves to Clean the Classroom
3699. Number of ZigZag Arrays I
3867. Sum of GCD of Formed Pairs
3875. Construct Uniform Parity Array I
3903. Smallest Stable Index I
3975. Filter Occupied Intervals

---

Generated by LeetLens — You're halfway done. Believe in Yourself ~K. 💖