DSA Factory
Curriculum
Level 1 · Foundations

Hashing

About 20 steps, from the first idea to a mastery test.

  1. Stage 0Seen before?Free
    1. 1A set remembers7 min
    2. 2A map counts8 min
    3. 3Count as you go8 min
    4. 4Look up the partner9 min
  2. Stage 1Grouping by keyFree
    1. 1Same key, same group9 min
    2. 2A consistent code9 min
    3. 3Letters to words9 min
    4. 4Groups of numbers9 min
  3. Stage 2Counting with mapsFree
    1. 1A map that slides9 min
    2. 2Pairs that differ by k9 min
    3. 3Meet in the middle10 min
    4. 4Count what came before10 min
  4. Stage 3Sets for structureFree
    1. 1What both lists share7 min
    2. 2In one but not the other7 min
    3. 3Have I been here before?8 min
    4. 4Many sets at once12 min
  5. Stage 4MasteryFree
    1. 1Shortest stretch, same degree12 min
    2. 2Neighbours in value10 min
    3. 3Pairs that fill up a k12 min
    4. 4Make every count different12 min
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