Method randrange

src/random.h:202–211

Generate a random integer in the range [0..range). * Precondition: range > 0. */

     * Precondition: range > 0.
     */
    uint64_t randrange(uint64_t range) noexcept
    {
        assert(range);
        --range;
        int bits = CountBits(range);
        while (true) {
            uint64_t ret = randbits(bits);
            if (ret <= range) return ret;
        }
    }

    /** Generate random bytes. */
    std::vector<unsigned char> randbytes(size_t len);