Trip-codes

What's a good way to generate trip codes like 4chan uses?  Taking the user IP as an argument.

>>62
You use them by never needing to find an element in them? Interesting way to COMPLETELY FUCKING IGNORE THE DOWNSIDE. Guess what? I never use a hashtable to hash anything, so the effective time is zero, much faster than a garray. Beat that. Also, rather ironically, if you use a modern compiler the difference in speed between a hashmap and an array should be neglible. I doubt you will test this yourself or consider something that doesn't agree with your "beliefs" but most modern compilers actually produce faster code for a std::vector than an array.