gistfile1.cpp

#include <iostream>
#include <fstream>
#include <string>

void gen_random(char *s, const int len) {
    static const char alphanum[] =
        "0123456789"
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
        "abcdefghijklmnopqrstuvwxyz";

    for (int i = 0; i < len; ++i) {
        s[i] = alphanum[rand() % (sizeof(alphanum) - 1)];
    }

    s[len] = 0;
}

int
main(int argc, char * argv[])
{
        char w1[13];
        char w2[13];

        for (std::size_t i = 0; i < 20000000; ++i) {
                gen_random(w1, 12);
                gen_random(w2, 12);
                std::cout << w1 << " : " << w2 << std::endl;
        }

        return 0;
}