[Update 10/21/2015: Changed the title from "six lines of C" to "462 bytes of C" to avoid endless arguments about what constitutes a line of C code.] [Update 6/28/2011: added Javascript version; press button below to see the output without compiling the code.] [Update 7/9/2011: if you're using a compiler other than gcc, you might need to put a #include <math.h> at the top for it to work correctly -