Algorithm Usage¶

Problems organized by the algorithms they use. Click links to view solution code.

Two Pointers (25 problems)¶

• 🟢 LeetCode 1 - Two Sum
• 🟢 LeetCode 21 - Merge Two Sorted Lists
• 🟢 LeetCode 26 - Remove Duplicates from Sorted Array
• 🟢 LeetCode 27 - Remove Element
• 🟢 LeetCode 88 - Merge Sorted Array
• 🟢 LeetCode 125 - Valid Palindrome
• 🟢 LeetCode 141 - Linked List Cycle
• 🟢 LeetCode 202 - Happy Number
• 🟢 LeetCode 283 - Move Zeroes
• 🟢 LeetCode 680 - Valid Palindrome II
• 🟢 LeetCode 876 - Middle of the Linked List
• 🟢 LeetCode 905 - Sort Array By Parity
• 🟢 LeetCode 922 - Sort Array By Parity II
• 🟢 LeetCode 977 - Squares of a Sorted Array
• 🟡 LeetCode 3 - Longest Substring Without Repeating Characters
• 🟡 LeetCode 11 - Container With Most Water
• 🟡 LeetCode 15 - 3Sum
• 🟡 LeetCode 16 - 3Sum Closest
• 🟡 LeetCode 75 - Sort Colors
• 🟡 LeetCode 80 - Remove Duplicates from Sorted Array II
• 🟡 LeetCode 142 - Linked List Cycle II
• 🟡 LeetCode 209 - Minimum Size Subarray Sum
• 🟡 LeetCode 340 - Longest Substring with At Most K Distinct Characters
• 🔴 LeetCode 4 - Median of Two Sorted Arrays
• 🔴 LeetCode 76 - Minimum Window Substring

Sliding Window (6 problems)¶

• 🟡 LeetCode 3 - Longest Substring Without Repeating Characters
• 🟡 LeetCode 209 - Minimum Size Subarray Sum
• 🟡 LeetCode 340 - Longest Substring with At Most K Distinct Characters
• 🟡 LeetCode 438 - Find All Anagrams in a String
• 🟡 LeetCode 567 - Permutation in String
• 🔴 LeetCode 76 - Minimum Window Substring

Greedy (2 problems)¶

• 🟢 LeetCode 680 - Valid Palindrome II
• 🟡 LeetCode 11 - Container With Most Water

Divide And Conquer (2 problems)¶

• 🔴 LeetCode 4 - Median of Two Sorted Arrays
• 🔴 LeetCode 23 - Merge k Sorted Lists

Sorting (2 problems)¶

• 🟡 LeetCode 15 - 3Sum
• 🟡 LeetCode 16 - 3Sum Closest

Binary Search (1 problems)¶

• 🔴 LeetCode 4 - Median of Two Sorted Arrays

Quickselect (1 problems)¶

• 🟡 LeetCode 215 - Kth Largest Element in an Array

Heap (1 problems)¶

• 🟡 LeetCode 215 - Kth Largest Element in an Array

Bfs (1 problems)¶

• 🟡 LeetCode 994 - Rotting Oranges

Recursion (1 problems)¶

• 🔴 LeetCode 25 - Reverse Nodes in k-Group

Math (1 problems)¶

• 🟢 LeetCode 202 - Happy Number

Backtracking (1 problems)¶

• 🔴 LeetCode 51 - N-Queens