Advent of Code 2025

#toyprogrammingchallenge

Okay, here is the challenge for this week.

Tennis is a cool sport to watch. Especially, if either Serena or Venus or both are playing. :) However, the scoring is really odd, because it is based on the clock face. To make it even more fun, it did come from France, so instead of Zero we refer to l'œuf or "the egg". However, as we now pronounce it , it is "love". I am certain that there can be some interesting jokes in there, but I am not going for any of them. :)

Anyway, when you begin a game both players have scored zero times so their score is said to be "love - love" or "love all". When a player has scored 1 time, they are said to have "15" as advancing around the clock face 1/4 of the way. Their second score would be called "30" since that would be 1/2 way around. Obviously, their third score should be "40" because that forces you to win by 2 :) Not sure it makes sense, but that is how it works. So as an example a game might go like this:

love - love
15 - love
30 - love
40 - love
Game - player1

Not all games work out that one player gets to run the score, so it could also go like this:
love - love
15 - love
15 - 15
15 - 30
30 - 30
30 - 40
Game - player2

However, after the 3rd point is scored if both players have 40 the score is said as
"Deuce"
Because, France. :)

At any point when a player becomes 2 points ahead after 40 they win, and we say Game - <player name>
But after the score is tied at 40 or higher, the next point is called "advantage" so we no longer care about the underlying clock face scores, and merely go through "Deuce", "Advantage - player1" "Deuce" "Advantage - player2" "Game - player2". In theory, one could continually bounce from "Deuce" to advantage one player or the other until one of them players simply falls out or dies. Though I am not aware of that ever actually happening. There have been some pretty long games.

"Back in 1975 on May 26, at the Surrey Grass Court Championships at Surbiton, Anthony Fawcett and Keith Glass racked up a record 37 deuces in a single game for a grand total of 80 points."

But I digress. Here is your challenge if you choose to accept it.

Write a method/function that takes any legal tennis game score, such as (0, 0) or (5,3) and so on, and have it output the traditional tennis score as described above, "love - love" or "Game - player1" in my example of legal scores. Keep in mind, (12, 2) is not a legal score, as once the first player achieved 4 he would have already won. You don't need to test for this, but be aware it is not a scenario you should have to deal with. You can represent any tie up to 2 simply as 'love - love' or '15 - 15' or '30 - 30' but starting at 3 you would not say '40 - 40' but rather "Deuce" at that level and any higher. If you would like to do so, as a bonus you could represent the simple ties less than 3:3 (Deuce) with the 'all' so 'love all', '15 all', or '30 all' would be a bonus representation, but '40 all' would be incorrect, as it should merely be 'Deuce'.

Use whatever language or methods you like. I am using Java. I will also have unit tests. You are free not to use them, but I am not interested in testing anyone's code for accuracy, so if you don't provide them, the best you can hope for is "Nice job. Good effort. I guess." At least from me :)
Try to focus on good quality code. Also focus on reduction of complexity, DRY, and certainly use subroutines as necessary.

Good Luck!!

I will probably be checking mine in to my GitHub or GitLab repo at some point later in the week.

#toyprogrammingchallenge

#toyprogrammingchallenge

Here should be a simple one. It was fun to do in Java and with chained calls it turns out to be somewhat of a one-liner. This is not a code-golf thing, but feel free to try it that way if that is your interest.

"Square Odd"
Let's process an integer. The idea is that if the number contains odd digits they need to be converted to their squared value. Even digits are passed through unchanged.

For example, given the number 232, you would output 292. Or in the case of 99, you would output 8181. But if it were 22 then the output would be 22.

If this is too simple and you would like a bit more of a challenge see if you can try a couple bonus situations.

1*. determine if a number is already in this state. For example 232 wouldn't be because 3 is not squared. However, 212 could be, as could 2814 since that could have come from 294.

and
2*. given a number possibly in this state already, decode it back to the original number.

Since 1 squared is 1 and some squares have even digits like 81 such a number could have started out as '9' or actually '81'. So in 1 and 2 you may want to come up with multiple initial beginnings. So given such '81' the answer would be both of those '81' and '9'.

#toyprogrammingchallenge

Things in my life have changed. I am now in a much larger focus on Java. I am still a huge fan of TDD and Test First, but I guess that is a religious thing so I will try to contain my zeal.

Initially the challenges were intended as small problems that should be in the 1-3 hour at most. As well, I focused towards Python and the problems I was using to learn the particular concepts I was working on at the time. Since my shift to Java I am less interested in some of the finer concepts and more interested in general issues. So even though I might find a solution that uses a whole pile of chained references interesting, its solution in some other language may not be nearly as interesting to you :)

I will try to be better about posting more often. Unless I find people aren't interested, in which case I won't waste the bandwidth :)

#toyprogrammingchallenge

I just boosted the last #toyprogrammingchallenge that I had posted from over a year ago.

I still think this is an interesting problem to solve. I have yet to attack it myself, but am definitely considering it. I have recently been doing a bunch more smaller exercises, and perhaps can post a few of those. Though I haven't necessarily written them, I have found them fun to do.

I do have some ideas, but for now I am waiting to see if anyone is even still interested in the #toyprogrammingchallenge puzzles anyway.

So you terraformed your marses and made yourself these perfectly square flat islands, on which you made bunch of single rover housing stations in a perfectly square NxM grids, and then randomly air dropped bunch of rovers there. Now you need a program to plan a course to get each of them to a place they can call home. Some of you went for the Electric Wheelchair 4.2 model, and others preferred the Atomic Tank 6.6.6.
1. EM 4.2: these are super efficient but have limited fuel, so need to make sure you do not ran out of it on any rover.
2. AT 6.6.6: these have unlimited fuel but wreck the environment, so gotta have them moving as little as possible altogether.
Rovers can't collide thanks to state of the art interdenominational wormhole technology, but it's proprietary and patented so you can't use it for anything other than avoiding collision.

For those who have no or too much imagination:

given an NxM grid and K (<= N*M) random points, both in the same range (say 0 to 1 on each axis), pair the random points to grid vertices minimizing the
1. maximum distance
2. sum of distances
between each pair.

#toyprogrammingchallenge

Tried a #toyprogrammingchallenge today, was pretty fun. @namark thanks for recommending these! I expect I’m gonna spend a lot of hours on these in the next few weeks.

#toyprogrammingchallenge

Okay, here's one with a story :) Let's see if this is entertaining enough :D

Here is a problem that involves being jerk.

You receive a parking ticket and decide to pay in the least
convient way possible... change. This decision comes to mind
because the tickets are in strange amounts because they use
the cents portion for some kind of internal encoding.

You decide to pay all in pennies but when you start to collect
them someone informs you that although change will be accepted,
if the counts of coins exceed the quantities required for a wrapper
then you must roll them.

US Coinage count to a roll
0.01 = 50
0.05 = 40
0.10 = 50
0.25 = 40
0.50 = 20
$1.00 = 25 (small) or 20 (large)

Question 1.
How many rolls and free coins of each can you provide to pay your
$100.37 ticket in order to use the highest count of unrolled coins?

Considering that a ticket can cost anywhere from $1.00 to $250.00.
You start telling everyone else about your plan and they decide to
play too, so you calculate how they should pay as well.

For example, 45 pennies 21 nickles for a $1.00 ticket might be
pretty obnoxious :).

Question 2. Which fine amount (in that range) would allow you to
provide the highest number of unrolled coins?

Question 3. The parking authority figures out what you are doing
and decides to change things up by hiring you. Your job is to
determine the best fine values to get paid in the least amount of
unrolled coins. What are those amounts what are those amounts (still
within that range of $1.00 to $250.00)

@Lossberg by the way, I do a #toyprogrammingchallenge here, you can look at the origination of it all the way back the 'Ninety-Nine Bottles of Beer" challenge. https://qoto.org/@Absinthe/102805659580967435

Feel free to play at any of them that interest you. There is no timebox on these. Watch for the tag #toyprogrammingchallenge and include it on any answers you offer to any of them.

La Fée Verte (@[email protected])

#toyprogrammingchallenge I want to propose a programming challenge. This could be fun for beginners and experienced programmers as well. It is language agnostic. It might even be more about community than the programming part itself. The challenge itself should not take more than an hour. But it shouldn't be so simple that you don't have to put in a little effort. I will propose the first one, and those who participate are welcome to propose the next and as we can agree on it we can go off and knock it out. Once you see other people's results you can modify your own, or even propose something to make someone else's better or faster or fix a bug that you find. These can become toy programs for you to have around for testing concepts, and helping to try out other languages. If you are interested or know someone else who might want to play too share this with them. I guess we can use this thread to get started, and I guess i am supposed to use a hashtag for something like this so how about #toyprogrammingchallenge I will try to work in Python at least in the beginning but you are welcome to work in whatever you are comfortable with. #toyprogrammingchallenge First challenge: "Ninety-nine bottles of beer on the wall" Generate the whole song from "Ninety-nine" to "No". The output should look like : Ninety-nine bottles of beer on the wall. Ninety-nine bottles of beer. Take one down, pass it around... Ninety-eight bottles of beer. (You know what the middle looks like) Two bottles of beer on the wall. Two bottles of beer. Take one down, pass it around... one bottle of beer. One bottle of beer on the wall. One bottle of beer. Take one down, pass it around... No bottles of beer. I won't put too many specifics on how you get there, but the output should be words, not numerals :) Try to write clean, maintainable and visually understandable code. Let see if I am alone or anyone wants to play along. :) Here is my first attempt total time 48 minutes. https://git.qoto.org/Absinthe/ninety_nine_bottles

qoto.org