Fastest possible summing numbers up to N

Posted by dada on Stack Overflow See other posts from Stack Overflow or by dada
Published on 2010-04-12T18:28:58Z Indexed on 2010/04/12 18:33 UTC
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Okay so i need really FAST algorithm or code in C if you have any it would be nice. The task is to sum all numbers from 1 to N for a given number N (it can be negative number too), so i did the usual way (you know just summing with loop from 1 to N) but it's not fast enough - i need something faster, i guess that i need the fastest possible way to do this.

If anyone could help me, please do. Thanks.

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Fastest possible summing numbers up to N - Developer IT

Fastest possible summing numbers up to N

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