mscroggs.co.uk
mscroggs.co.uk

subscribe

Blog

Christmas (2024) is coming!

 2024-11-21 
The mscroggs.co.uk Advent Calendar is back for its tenth year! Behind each door, there will be a puzzle with a three digit solution. The solution to each day's puzzle forms part of a logic puzzle:
It's nearly Christmas and something terrible has happened: there's been a major malfunction in multiple machines in Santa's toy factory, and not enough presents have been made. Santa has a backup warehouse full of wrapped presents that can be used in the case of severe emergency, but the warehouse is locked. You need to help Santa work out the code to unlock the warehouse so that he can deliver the presents before Christmas is ruined for everyone.
The information needed to work out the code to the warehouse is known by Santa and his three most trusted elves: Santa is remembering a three-digit number, and each elf is remembering a one-digit and a three-digit number. If Santa and the elves all agree that the emergency warehouse should be opened, they can work out the code for the door as follows:
But this year, there is a complication: the three elves are on a diplomatic mission to Mars to visit Martian Santa and cannot be contacted, so you need to piece together their numbers from the clues they have left behind.
Behind each day (except Christmas Day), there is a puzzle with a three-digit answer. Each of these answers forms part of a clue about Santa's and the elves' numbers. You must use these clues to work out the code for the warehouse. You can use this page to try opening the door. If you enter an incorrect code three times, the door mechanism locks until the following day.
Ten randomly selected people who solve all the puzzles, open the warehouse, and fill in the entry form behind the door on the 25th will win prizes!
The prizes will include an mscroggs.co.uk Advent 2024 T-shirt. If you'd like one of the T-shirts from a previous Advent, they are available to order at merch.mscroggs.co.uk.
The winners will be randomly chosen from all those who submit the entry form before the end of 2024. Each day's puzzle (and the entry form on Christmas Day) will be available from 5:00am GMT. But as the winners will be selected randomly, there's no need to get up at 5am on Christmas Day to enter!
As you solve the puzzles, your answers will be stored. To share your stored answers between multiple devices, enter your email address below the calendar and you will be emailed a magic link to visit on your other devices.
To win a prize, you must submit your entry before the end of 2024. Only one entry will be accepted per person. If you have any questions, ask them in the comments below, on Bluesky, or on Mastodon. If you'd like to chat with other solvers, we'll be discussing the Advent Calendar in the #scroggs-advent-calendar channel in the Finite Group Discord: you can join the Discord by following the link in this post on Patreon (you'll need to become a free member on Patreon to unlock the post).
So once December is here, get solving! Good luck and have a very merry Christmas!
×9      ×2                  ×2
(Click on one of these icons to react to this blog post)

You might also enjoy...

Comments

Comments in green were written by me. Comments in blue were not written by me.
@Ben: Thanks, I've added the "before"
Matthew
   ×2              Reply
I am so appreciative that you continue to make these puzzles every year. I think I started doing them in 2017 and always enjoy them. Thank you!
Jessica
×2                 Reply
Thanks Scroggs - first time I've done this and very much enjoyed the days and also the meta-puzzling. Brilliant!!. If you run in future years I have one request for a tiny tweak - I find the numbers on the advent calendar for the days very small for my ageing eye-sight - any chance of a bigger font? And last suggestion - when it gets to the end, provide a link to your "buy me a cup of tea" page as this is more than worth a few £s :-). Thanks again :-)
Justin
×1                 Reply
@Seth Cohen: Thanks Seth, I solved it by looking at the 5×5 picture and thinking harder. Thanks to Matthew for another enjoyable set of puzzles. I look forward to reading the proper solution.
Reza
                 Reply
Had a great time doing this puzzles again this year! 23 was particularly fun :) Thanks for taking the time to make this!
Bill V.
                 Reply
I enjoyed working the advent puzzles. Thank you for providing such fun entertainment and math challenges! Attempted most without any programming help but some begged for a programming solution. Refreshed some former Python skills to happily solve a few puzzles. Looking forward to math solutions. Merry Christmas and Happy Holidays!
Tony
×1                 Reply
 Add a Comment 


I will only use your email address to reply to your comment (if a reply is needed).

Allowed HTML tags: <br> <a> <small> <b> <i> <s> <sup> <sub> <u> <spoiler> <ul> <ol> <li> <logo>
To prove you are not a spam bot, please type "w" then "i" then "d" then "t" then "h" in the box below (case sensitive):

Archive

Show me a random blog post
 2026 

May 2026

World Cup stickers 2026

Apr 2026

A new puzzle every day
Mixing Wordle with other games

Feb 2026

Christmas (2025) is over
 2025 

Dec 2025

Christmas card 2025

Nov 2025

Christmas (2025) is coming!

Sep 2025

The partridge puzzle

Aug 2025

TMiP 2025 puzzle hunt

Jun 2025

A nonogram alphabet

Mar 2025

How to write a crossnumber

Jan 2025

Christmas (2024) is over
Friendly squares
 2024 

Dec 2024

A regular expression Christmas puzzle
Christmas card 2024

Nov 2024

Christmas (2024) is coming!

Feb 2024

Zines, pt. 2

Jan 2024

Christmas (2023) is over
 2023 
▼ show ▼
 2022 
▼ show ▼
 2021 
▼ show ▼
 2020 
▼ show ▼
 2019 
▼ show ▼
 2018 
▼ show ▼
 2017 
▼ show ▼
 2016 
▼ show ▼
 2015 
▼ show ▼
 2014 
▼ show ▼
 2013 
▼ show ▼
 2012 
▼ show ▼

Tags

logo stirling numbers python sobolev spaces estimation turtles tmip books crossnumbers boundary element methods realhats menace wordle gather town computational complexity fonts game of life matrix of cofactors mathsteroids fractals partridge puzzle game show probability data visualisation errors christmas curvature binary radio 4 manchester folding paper gaussian elimination nonograms statistics go numerical analysis puzzles draughts thirteen european cup map projections convergence machine learning approximation inverse matrices alphabets national lottery hexapawn friendly squares flexagons platonic solids wool newcastle bempp chalkdust magazine geogebra rhombicuboctahedron pascal's triangle arrangement puzzles runge's phenomenon noughts and crosses chess captain scarlet bubble bobble video games coins regular expressions gerry anderson pizza cutting signorini conditions squares nine men's morris hats light rugby pythagoras ternary countdown oeis kenilworth arithmetic weather station frobel youtube cambridge latex golden ratio pi fence posts databet logic weak imposition anscombe's quartet talking maths in public probability crochet triangles pi approximation day matt parker 24 hour maths rust reddit kings zines error bars christmas card numbers raspberry pi stickers mean exponential growth determinants propositional calculus accuracy graphs news folding tube maps geometry football polynomials the aperiodical golden spiral craft edinburgh wave scattering pokémon asteroids sorting finite element method dataset simultaneous equations preconditioning hannah fry php trigonometry bluesky pokémon wordle ucl world cup inline code hyperbolic surfaces warwick electromagnetic field recursion bodmas data a gamut of games reuleaux polygons bots martin gardner interpolation sound final fantasy pac-man live stream tennis dates correlation sport mathslogicbot royal baby london underground plastic ratio quadrilaterals harriss spiral javascript london matrix of minors standard deviation graph theory phd programming big internet math-off misleading statistics manchester science festival games matrices matrix multiplication dinosaurs crosswords royal institution speed chebyshev crossnumber braiding datasaurus dozen advent calendar dragon curves tetris cross stitch palindromes people maths mathsjam guest posts coventry logs finite group

Archive

Show me a random blog post
▼ show ▼
© Matthew Scroggs 2012–2026