ACCU C++ Countdown Pub Quiz

The ACCU conference is one of the highlights of my year. I ran a brand new session, a C++ Pub Quiz with an emphasis on fun and interaction, based loosely on the popular UK TV game show Countdown.

In the TV version, contestants play individually and have 30 seconds to find the longest word using only a small set of letters. In this version, contestants play in teams, and have ~7 minutes to write the smallest valid C++ program containing a small set of tokens.

For example, if the tokens were:
catch -> [ ; -- foobar operator

Then a winning program (53 characters long) might be:
class c { c operator->(){ foobar: try{ } catch(c x[]){ x--; } } };

This might not sound very interesting but it the format works. Here's what some of the participants said:
Pub quiz countdown was enormous fun. It showed me what C++ features I don’t really use very often and allowed me to deploy some very sneaky tricks that I wouldn’t touch in production code. Everyone should play it. At least once. With their boss. (Guy Davidson, Coding Manager, Creative Assembly)
This session was one of the highlights of the conference for me: it was so much fun! It was an extremely entertaining session and I really hope to see similar ideas in the future.
(Vittorio Romeo, Bloomberg)
The format was really great; it encouraged healthy competition and allowed for some pretty heroic submissions, but it also kept the barrier for entry very low so that everyone could take part. I especially enjoyed seeing the ridiculous hacks which others would employ so that I could unceremoniously steal them for the next round. (Simon Brand, Senior Software Engineer, Codeplay Software Ltd)
The “Countdown pub quiz” was a combination of excellent geeky fun, fiendish puzzle, and competitive challenge. If you have a group of C++ programmers who enjoy the language, are playful, and want to improve their skills, I’d highly recommend getting involved. (Pete Goodliffe)
Not being a fan of the original Countdown TV programme, I was dubious about its use as a C++ teaching format. I needn't have worried - the session was engaging, enjoyable and educational. (Seb Rose, Cucumber)

We used cyber-dojo with some custom C++17 start-points which automatically told you your program's size and score. The rules were as follows:
  • The judges decision was final
  • Only non-whitespace characters were counted
  • Programs had to compile
  • Warnings were allowed
  • Extra tokens were allowed
  • Each token has to be a single whole token. For example the . token had to be the member access token; you could not use ... ellipsis or 4.2 floating point literal

The winners and the tokens were as follows (can you find smaller programs?)
Round 1: snakes, 75 character program, dynamic_cast snafu += return switch final
Round 2: wolves,koalas tied, 54 character program, catch ; foobar operator -- [
Round 3: frogs, 62 character program, else ~ default -> using foobar 0x4b
Round 4: tigers, 44 character program, string include for auto template 42
Round 5: pandas, tigers tied, 82 character program, virtual typename x reinterpret_cast static_cast 30ul
Round 6: wolves, 64 character program, constexpr override goto wibble . this
The raccoons and lions won the conundrum rounds.

The result was very close.
In 3rd place snakes with 481 points.
In 2nd place alligators with 488 points.
In 1st place tigers with 495 points.
A big thank you to my co-presenter Rob Chatley, to all the contestants for being such good sports, and to Bloomberg for sponsoring the Quiz.