Go Through the Question Bank Breadth-First, not Depth-First

An easy trick to improve your retention while working through a bank of review or challenge problems like LeetCode, HackerRank, etc.

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Here’s an easy trick to improve your retention while working through a bank of review or challenge problems like LeetCode, HackerRank, etc:

Go through the question bank breadth-first, not depth-first.

For instance, don’t spend a whole day on divide-and-conquer problems. Instead, cycle through all the categories doing one problem and then moving to the next category.

This approach naturally leverages two cognitive learning strategies:

1) SPACED REVIEW

When reviews are spaced out or distributed over multiple sessions (as opposed to being crammed or massed into a single session), memory is not only restored, but also further consolidated into long-term storage, which slows its decay. This is known as the spacing effect.

2) INTERLEAVING, a.k.a mixed/varied practice

Interleaving involves spreading minimal effective doses of practice across various skills, in contrast to blocked practice, which involves extensive consecutive repetition of a single skill.

can give a false sense of mastery and fluency because it allows students to settle into a robotic rhythm of mindlessly applying one type of solution to one type of problem.

, on the other hand, creates a “desirable difficulty” that promotes vastly superior retention and generalization, making it a more effective review strategy.

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