with a binary tree, you get O(log n) instead of O(1) for each operation
Well, only if the binary tree is balanced (and ordered). I am very well aware of the performance levels of a binary tree - if I wanted to settle for O (log n) performance, I wouldn't have posted the challenge. The challenge is to do all operations in O (1) - doing one or more in O (log n) is not a challenge.
Notice however, that if you use such a data structure only once, and you use the efficent C implementation, the OS still has to initialize the array when the process gets the memory by calling brk or mmap.
While some C libraries might initialize the memory claimed with mmap or brk, there's no reason they have to. The OS and/or the C libraries can always be patched that one can claim a segment of memory, and taking it "as is". For the scope of the challenge, you may assume that we run on a platform where memory is given out "as is".

Abigail

In reply to Re: Data structure challenge by Abigail-II
in thread Data structure challenge by Abigail-II

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