Finding The Observation

Small cases, working backwards, reformulating, symmetry, relaxing a constraint, and counting from the other side.

0 / 3 solved

Question Tags Difficulty Success

1. Count The Minimum Once

contribution-techniquereframing +2

Medium —

2. Two Corners One Colour

invariantscoloring-argument +2

Medium 60%

3. Zero Two Seven Nine

small-casespattern-finding +2

Medium 50%

Learning Resources

Polya's four steps: devise a plan and its heuristics

Jeff Erickson, Recursion chapter (reduce and delegate)

The Algorithm Design Manual, war stories and design methodology

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