Two-line summary. Solve Blind 75 in 4 weeks by pattern (not by problem number). Re-solve weak patterns until you can derive them cold. Most people fail because they shotgun-solve in random order.
Why Blind 75?
Blind 75 is a curated list of 75 LeetCode problems that originally appeared on Reddit in 2020. It became the canonical "first list" for SDE interview prep because the problems span every major pattern: arrays, two pointers, sliding window, hash map, intervals, linked list, stack, binary search, trees, tries, graphs, dynamic programming, and bit manipulation.
Cover Blind 75 and you can convincingly tackle 80% of FAANG-style first rounds.
Why most people fail Blind 75
They treat it as a checklist. Problem 1, problem 2, problem 3 — tick, tick, tick. Then in the interview they freeze because they memorised solutions instead of recognising patterns.
The fix: group by pattern, not by list order. Solve all the "two pointer" problems back-to-back. Then sliding window. Then binary search. Your brain will start to see the pattern in the problem statement, which is the entire skill being tested.
The 4-week plan
Week 1 — Foundations + Easy patterns
- Arrays + hashing (Two Sum, Valid Anagram, Group Anagrams, Top K Frequent, Contains Duplicate)
- Two pointers (Valid Palindrome, 3Sum, Container With Most Water)
- Sliding window (Best Time to Buy/Sell Stock, Longest Substring Without Repeating)
- Stack (Valid Parentheses, Min Stack, Daily Temperatures)
Week 2 — Binary search + linked list + trees
- Binary search (Find Minimum in Rotated Sorted Array, Search in Rotated Sorted Array)
- Linked list (Reverse Linked List, Linked List Cycle, Merge Two Sorted Lists, Reorder List)
- Trees (Invert Binary Tree, Max Depth, Same Tree, Subtree, Lowest Common Ancestor, Level Order Traversal, Validate BST)
Week 3 — Trie + heap + graphs
- Trie (Implement Trie, Add and Search Word, Word Search II)
- Heap / Priority Queue (Find Median from Data Stream, Top K Elements)
- Graph (Number of Islands, Clone Graph, Pacific Atlantic Water Flow, Course Schedule)
- Backtracking (Combination Sum, Word Search)
Week 4 — Dynamic programming + revision
- 1-D DP (Climbing Stairs, House Robber, Longest Increasing Subsequence, Word Break)
- 2-D DP (Unique Paths, Longest Common Subsequence)
- Greedy + intervals + math + bit-manipulation
- Re-solve weak patterns from weeks 1–3
How to study each problem
- Spend 25 min attempting it on your own. Set a timer.
- If stuck, read the pattern hint, not the full solution.
- If still stuck after 35 min total, read the optimal solution.
- Close everything. Re-implement from scratch. Until it compiles and passes, you don't know it.
- Write 1 paragraph in your own words explaining the pattern. Save in a notes file.
Mock interviews
At the end of Week 2, start doing 2 mock interviews per week. Use a friend, your college senior, or a free service like Pramp. The first 5 mocks will be brutal — that's the point. By mock 15 you'll be calm.
Hindi-friendly resources (free)
- Techwave Academy — Blind 75 (Hindi explanations)
- NeetCode 150 — Complete SDE Prep (graduate to this after Blind 75)
- Two Sum — Hindi walk-through
- Sliding Window Pattern (Hindi)
- Dynamic Programming (Hindi)
What to do after Blind 75
NeetCode 150 (deeper pattern coverage), then problem-specific lists by company (search "Amazon LeetCode tagged" — usually 50-100 problems). At that point you're ready for on-site loops.
Tone advice
Don't grind 8 hours/day. You'll burn out. 2 hours of focused practice beats 6 hours of mindless solving. Sleep, recovery, and re-solving weak problems matter more than chasing the problem count.
Good luck. Drop a comment on our course page if a specific problem trips you up.