efficient way of searching a character in a set of character C language

I have a set of characters, minimum hundreds of characters. How could i get the position 开发者_如何学编程of a particular character in that list efficiently.

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If you set of characters is sorted, you can use bsearch().

If not, you're pretty much out of luck - you'll have to use a simple scan, like strchr().

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convert the set into a ordered list and use binary search.