> It wasn't clear from the problem whether just the sum was needed or the whole path. This just returns 8

any approach recording paths will fail in general, because there is no guaranty for a unique or even small number of optimal solutions.

Just imagine a triangle with n=100 rows but only weight 1 in every cell, the number of optimal paths is 2**99 then and the weight is always 100.

But it's nonetheless possible to calculate the weight of the optimal path, and even to reconstruct one of those optimal path.

And this in at most n**2/2 (here ~5000) steps (time and space complexity)

see Re^2: Brute force vs algorithm (PWC # 100)

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: Brute force vs algorithm (PWC # 100) by LanX
in thread Brute force vs algorithm (PWC # 100) by 1nickt

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