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Lesson 6 of 9 · Arrays and the Array Methods: The map, filter, reduce Pipeline

Module 7 · Arrays and the Array Methods: The map, filter, reduce Pipeline

The Contest and Interview Pack: Two-Sum, Sliding Windows, Prefix Sums, Flatten and Chunk

ProReading

Contest problems and interview questions about arrays repeat a small set of ideas. The first idea that comes to mind is usually right but slow: try every pair, or recompute every window. With n at a hundred thousand, "every pair" is five billion steps, and the judge stops you at two seconds.

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What is inside The Contest and Interview Pack: Two-Sum, Sliding Windows, Prefix Sums, Flatten and Chunk

  1. Pattern 1: two-sum with a Map
  2. Pattern 2: the sliding window
  3. Pattern 3: prefix sums
  4. Pattern 4: flatten without flat
  5. Pattern 5: chunking
  6. Six interview questions