And - your last link does not even mention hashes. Bother explain what is doing here? TIA!

Look at the table

Here are some well-known algorithms and their order functions (adapted from [2]): 
Notation       Name       Example
O(1)       constant       array or hash index

[download]

...

2. Kernighan, B. W. & Pike, R., (1999). The Practice of Programming, p. 41. Addison-Wesley.

yes. I am sure.

Great, prove it :)

In reply to Re^4: "Just use a hash": An overworked mantra? by Anonymous Monk
in thread "Just use a hash": An overworked mantra? by davido

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