Free to read · 22 interview patterns

Build a memory palace for the patterns interviews keep asking.

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Scroll the tour: one illustrated room for every pattern the app teaches. Open any pattern to walk its memory room.

  1. Two sum II (sorted) Arrays
  2. Valid palindrome Strings
  3. Build a frequency table Hash Maps
  4. Reverse linked list Linked Lists
  5. Validate parentheses Stacks & Queues
  6. Tree traversals Trees
  7. Implement trie methods Tries
  8. Heap operations Heaps
  9. Search a sorted matrix Matrices
  10. Department top three salaries Database
  11. Subsets Backtracking
  12. Number of Islands Graphs
  13. Topological sort (DFS post-order) Graphs
  14. Binary search Binary Search
  15. Climbing Stairs Dynamic Programming
  16. Edit Distance Dynamic Programming
  17. Interval scheduling (activity selection) Greedy
  18. Minimum window substring Sliding Window
  19. 3Sum Sorting
  20. Merge intervals Intervals
  21. Subarray sum equals k Prefix Sum
  22. Pow(x, n) Math
  23. File line iterator Streams & I/O
  24. LRU cache System Design

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