🚀 DSA LeetCode Roadmap 📌 Phase 1: Arrays & Hashing Goal: Build strong fundamentals in arrays, hashmaps, and frequency counting.
Two Sum – Easy 🔗 https://leetcode.com/problems/two-sum/description/
Contains Duplicate – Easy 🔗 https://leetcode.com/problems/contains-duplicate/description/
Valid Anagram – Easy 🔗 https://leetcode.com/problems/valid-anagram/description/
Group Anagrams – Medium 🔗 https://leetcode.com/problems/group-anagrams/description/
Top K Frequent Elements – Medium 🔗 https://leetcode.com/problems/top-k-frequent-elements/description/
Product of Array Except Self – Medium 🔗 https://leetcode.com/problems/product-of-array-except-self/description/
Maximum Subarray – Medium 🔗 https://leetcode.com/problems/maximum-subarray/description/
Merge Intervals – Medium 🔗 https://leetcode.com/problems/merge-intervals/description/
3Sum – Medium 🔗 https://leetcode.com/problems/3sum/description/
Container With Most Water – Medium 🔗 https://leetcode.com/problems/container-with-most-water/description/
📌 Phase 2: Two Pointers Goal: Learn to solve problems with two indices moving through the array.
Valid Palindrome – Easy 🔗 https://leetcode.com/problems/valid-palindrome/description/
Two Sum II – Input Array Is Sorted – Medium 🔗 https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/
3Sum – Medium 🔗 https://leetcode.com/problems/3sum/description/
Container With Most Water – Medium 🔗 https://leetcode.com/problems/container-with-most-water/description/
Trapping Rain Water – Hard 🔗 https://leetcode.com/problems/trapping-rain-water/description/
📌 Phase 3: Sliding Window Goal: Optimize subarray problems with sliding window.
Best Time to Buy and Sell Stock – Easy 🔗 https://leetcode.com/problems/best-time-to-buy-and-sell-stock/description/
Longest Substring Without Repeating Characters – Medium 🔗 https://leetcode.com/problems/longest-substring-without-repeating-characters/description/
Longest Repeating Character Replacement – Medium 🔗 https://leetcode.com/problems/longest-repeating-character-replacement/description/
Minimum Window Substring – Hard 🔗 https://leetcode.com/problems/minimum-window-substring/description/
📌 Phase 4: Stack Goal: Understand monotonic stacks and parsing problems.
Valid Parentheses – Easy 🔗 https://leetcode.com/problems/valid-parentheses/description/
Min Stack – Medium 🔗 https://leetcode.com/problems/min-stack/description/
Evaluate Reverse Polish Notation – Medium 🔗 https://leetcode.com/problems/evaluate-reverse-polish-notation/description/
Generate Parentheses – Medium 🔗 https://leetcode.com/problems/generate-parentheses/description/
Daily Temperatures – Medium 🔗 https://leetcode.com/problems/daily-temperatures/description/
Car Fleet – Medium 🔗 https://leetcode.com/problems/car-fleet/description/
Largest Rectangle in Histogram – Hard 🔗 https://leetcode.com/problems/largest-rectangle-in-histogram/description/
📌 Phase 5: Binary Search Goal: Learn standard and advanced binary search patterns.
Binary Search – Easy 🔗 https://leetcode.com/problems/binary-search/description/
Search a 2D Matrix – Medium 🔗 https://leetcode.com/problems/search-a-2d-matrix/description/
Koko Eating Bananas – Medium 🔗 https://leetcode.com/problems/koko-eating-bananas/description/
Find Minimum in Rotated Sorted Array – Medium 🔗 https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/description/
Search in Rotated Sorted Array – Medium 🔗 https://leetcode.com/problems/search-in-rotated-sorted-array/description/
Median of Two Sorted Arrays – Hard 🔗 https://leetcode.com/problems/median-of-two-sorted-arrays/description/
📌 Phase 6: Linked List Goal: Master linked list basics and fast/slow pointer tricks.
Reverse Linked List – Easy 🔗 https://leetcode.com/problems/reverse-linked-list/description/
Merge Two Sorted Lists – Easy 🔗 https://leetcode.com/problems/merge-two-sorted-lists/description/
Reorder List – Medium 🔗 https://leetcode.com/problems/reorder-list/description/
Remove Nth Node From End of List – Medium 🔗 https://leetcode.com/problems/remove-nth-node-from-end-of-list/description/
Linked List Cycle – Easy 🔗 https://leetcode.com/problems/linked-list-cycle/description/
LRU Cache – Medium 🔗 https://leetcode.com/problems/lru-cache/description/
Merge K Sorted Lists – Hard 🔗 https://leetcode.com/problems/merge-k-sorted-lists/description/