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Problem list

Blind 75

The Blind 75 originated from a viral post on Blind (anonymous workplace app) where an engineer shared the 75 problems they believed cover all essential patterns for coding interviews. It became the gold standard for efficient interview prep.

Recommended schedule

6 blocks
  1. 01Week 1Arrays, Two Pointers14 problems
  2. 02Week 2Sliding Window, Stack13 problems
  3. 03Week 3Binary Search, Linked List13 problems
  4. 04Week 4Trees11 problems
  5. 05Week 5Graphs, Backtracking11 problems
  6. 06Week 6DP, Heap, Tries13 problems

Problems by pattern

12 patterns

  • Arrays & Hashing

    9 problems

    Two Sum · Contains Duplicate · Valid Anagram · Group Anagrams · Top K Frequent Elements · Product of Array Except Self · Valid Sudoku · Encode and Decode Strings · +1 more

  • Two Pointers

    5 problems

    Valid Palindrome · 3Sum · Container With Most Water · Two Sum II · Trapping Rain Water

  • Sliding Window

    6 problems

    Best Time to Buy and Sell Stock · Longest Substring Without Repeating · Longest Repeating Character Replacement · Permutation in String · Minimum Window Substring · Sliding Window Maximum

  • Stack

    7 problems

    Valid Parentheses · Min Stack · Evaluate Reverse Polish Notation · Generate Parentheses · Daily Temperatures · Car Fleet · Largest Rectangle in Histogram

  • Binary Search

    7 problems

    Binary Search · Search a 2D Matrix · Koko Eating Bananas · Find Minimum in Rotated Sorted Array · Search in Rotated Sorted Array · Time Based Key-Value Store · Median of Two Sorted Arrays

  • Linked List

    6 problems

    Reverse Linked List · Merge Two Sorted Lists · Linked List Cycle · Reorder List · Remove Nth Node From End of List · Merge k Sorted Lists

  • Trees

    11 problems

    Invert Binary Tree · Maximum Depth of Binary Tree · Same Tree · Subtree of Another Tree · Lowest Common Ancestor of BST · Binary Tree Level Order Traversal · Validate BST · Kth Smallest Element in BST · +3 more

  • Tries

    3 problems

    Implement Trie (Prefix Tree) · Design Add and Search Words · Word Search II

  • Heap / Priority Queue

    3 problems

    Kth Largest Element in a Stream · Last Stone Weight · K Closest Points to Origin · Kth Largest Element in an Array · Task Scheduler · Design Twitter · Find Median from Data Stream

  • Backtracking

    5 problems

    Subsets · Combination Sum · Permutations · Subsets II · Combination Sum II · Word Search · Palindrome Partitioning · Letter Combinations of a Phone Number · +1 more

  • Graphs

    6 problems

    Number of Islands · Clone Graph · Pacific Atlantic Water Flow · Course Schedule · Number of Connected Components in Undirected Graph · Graph Valid Tree

  • Dynamic Programming

    7 problems

    Climbing Stairs · House Robber · House Robber II · Longest Palindromic Substring · Palindromic Substrings · Decode Ways · Coin Change · Maximum Product Subarray · +3 more

Study tips

5
  • Do problems in pattern order, not difficulty order
  • Spend max 45 min on a problem before checking the solution
  • After solving, explain the approach out loud
  • Review problems you got wrong after 1 day, 3 days, and 7 days
  • Focus on understanding patterns, not memorizing solutions