Re^2: Turning very larger numbers into an array of bits

Factorial : There are n! ways of arranging n distinct objects into an ordered sequence.

With 80 objects,

n! = 80!
= 7.156945704 E+118
=71569457046263802294811533723186532165584657342365752577109445058227039255480148842668944867280814080000000000000000000
There is no program/computer that can do that many tests. This is a humongous number.

You have absolutely no chance at all without a strategy to reduce the number of tests. A better explanation of what you are testing will probably yield massive orders of magnitude in reduction of computations. Without that, I see ZERO chance.

Comment on Re^2: Turning very larger numbers into an array of bits

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Re^3: Turning very larger numbers into an array of bits by BrowserUk (Patriarch) on Feb 06, 2017 at 06:23 UTC
There are n! ways of arranging n distinct objects into an ordered sequence. That would only be true if the OP allowed duplicates; Ie. if a set consisting of 80 x bit 0 was allowed, but the OP does state: How would you quickly iterate over every combination of an array with 80 elements where each element is used a maximum of once* in the combination?* Thus the maximium number of sets is 2^80. He also made no mention of "ordered". With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity. In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]

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Re^3: Turning very larger numbers into an array of bits
by BrowserUk (Patriarch) on Feb 06, 2017 at 06:23 UTC

There are n! ways of arranging n distinct objects into an ordered sequence.

That would only be true if the OP allowed duplicates; Ie. if a set consisting of 80 x bit 0 was allowed, but the OP does state:

How would you quickly iterate over every combination of an array with 80 elements where each element is used a maximum of once in the combination?

Thus the maximium number of sets is 2^80.

He also made no mention of "ordered".

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity.

In the absence of evidence, opinion is indistinguishable from prejudice.

[reply]