But that's all irrelevant. Your random number generator is likely to only have 24, 32, 48 or 64 bits of entropy. Which means that most of the possible strings will never be generated. Even with 64 bits of entropy, there are only 18446744073709551616 strings possible. Which makes is far more likely for collisions to happen.

That would only be the case if he was only calling rand() once to pick from the 6.45e44 strings. But he is calling rand 25 times. Which as each pick is 'independant' of the previous and next picks, it increases the effective entropy.

By way of proof. If you throw a die once, you can only get 1 .. 6; but throw it twice and you can get 1 .. 36.

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

The start of some sanity?

In reply to Re^2: How likely is rand() to repeat? by BrowserUk
in thread How likely is rand() to repeat? by desertrat

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