An automated algorithm tool for running time

I am wondering if there is an open source project that can run the algorithm and tell us what the running time is (just need to know the Big-Oh running time).

I know I can do this with hands, but a lot of algorithms are too long or too complex to actually trace the running time.

Thanks.

PS: Mainly for C++ (but it works for more than just C++ 开发者_开发技巧would be nice!!)

There's just no way to do this. You'll never know generally what set of n you have to test for any given algorithm. For example sin and linear will look almost identical at small values of t (the input). Exponential can look polynomial in various ranges of input. For other functions, the constant time may make a linear function look sublinear.

The way to figure out the big-oh complexity is to just analyze the algorithm yourself.