[gcanyon]

I fell deep into this trap just yesterday, solving a Project Euler problem in Python. It involved a 2-million+ digit number. I'm just starting with Python, and while I know it transparently handles large integers, out of an abundance of caution I spent an hour optimizing to avoid dealing with greater-than-64-bit values, since the result needed is modulo a <64 bit value.

My code ran in about 4 seconds.

Then I thought I'd try a slightly larger optimization that involved ~128 bit values. That ran in a second, so obviously the switch to large integers either doesn't happen at 64 bits, or Python just handles it really well.

Then I thought to just do the math and let Python sort the results. One line of Python. Took ~20 seconds to write. Calculated the 2-million digit number and then did the modulo. Ran in a small fraction of a second. <sigh>