Memoize only reduces the work, it doesn't eliminate checking to see if it's already done.

For N=1000, 2^n ~~ 1e301, while n^2/2 ~~ 1e5. The first will never finish in the lifetime of the universe, the second in a blink of an eye.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^3: Puzzle: Given an array of integers, find the best sequence of pop / shift... by QM
in thread Puzzle: Given an array of integers, find the best sequence of pop / shift... by TedPride

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