Codebusters C

[will0416]

I just did one and it worked just like you described it. Thank you so much!

No problem

[xiangyu]

Generally, what is conaidered a good time for the timed bonus question?

[Name]

Generally, what is considered a good time for the timed bonus question?

Depends on question. Generally 2-4 min on a average difficulty timed question is good. There are some super long and weird quotes where like 5-6 min is good, and on easier quotes teams will probably be getting sub 2 min (I could see sub 1 min if its really easy). But I think a consistent 2-4 min solve would be a good benchmark.

[Vortexx2]

So I've seen quite a few tests that have questions like this and I wanted ti know if it is a mistake or if it isn't, how to solve it. For codes like Morbit and Pollux, you're supposed to be given 6 hint digits. Usually its like 1=--, 2=.-, 4=-x...etc. However, on some tests it just says "hint digits:024579" without giving any of the marks. Is this a mistake?

[l0lit]

So I've seen quite a few tests that have questions like this and I wanted ti know if it is a mistake or if it isn't, how to solve it. For codes like Morbit and Pollux, you're supposed to be given 6 hint digits. Usually its like 1=--, 2=.-, 4=-x...etc. However, on some tests it just says "hint digits:024579" without giving any of the marks. Is this a mistake?

I think this is for the Morbit cipher. When encoding using Morbit, you use a 9-letter keyword and then under each letter you put what order it is in the alphabet. For example QUESTIONS in order would result in EINOQSSTU so E=1, I=2, N=3, etc. Thus the original key of QUESTIONS --> 591682437. It is then overlaid on a predetermined key in order of .-x, so 5=.. 9=.- 1=.x 6=-. etc. So what it is likely doing is saying 0=.. 2 =.- 4=.x etc.
The full order is .. .- .x -. -- -x x. x- xx
You can see this on the official definition page as stated by the rules.

[Apple5775]

I have two questions for the timed question:
1. When is a timed question too long and not worth everyone's time? In the two NY tests I have taken, the timed question has been very long. The regionals test had a E count around 20 but had a long hint similar to "Dear Johnny" or something. We did it in 6:40. In states, however, the E count was in the mid/high 20s and by the time we finished the cipher it was just after 10 minutes. It seems like no one else in the room was attempting it/smartly bailed out. Is there an approximate cutoff such as around 220+ letters where we shouldn't attempt it?

2. How do you work together to get faster on timed questions? Together, we can do timed anywhere from 4:30 to 7:30, but that isn't much faster than individually. How do we increase our efficiency together - should there be roles for each person? Right now we have 2 people writing because 3 gets hectic space wise. Our starts are sometimes slow and filling in letters always takes a long time. It almost seems impossible to write all the letters in under 2 minutes unless everyone is constantly writing.

[Name]

I have two questions for the timed question:
1. When is a timed question too long and not worth everyone's time? In the two NY tests I have taken, the timed question has been very long. The regionals test had a E count around 20 but had a long hint similar to "Dear Johnny" or something. We did it in 6:40. In states, however, the E count was in the mid/high 20s and by the time we finished the cipher it was just after 10 minutes. It seems like no one else in the room was attempting it/smartly bailed out. Is there an approximate cutoff such as around 220+ letters where we shouldn't attempt it?

2. How do you work together to get faster on timed questions? Together, we can do timed anywhere from 4:30 to 7:30, but that isn't much faster than individually. How do we increase our efficiency together - should there be roles for each person? Right now we have 2 people writing because 3 gets hectic space wise. Our starts are sometimes slow and filling in letters always takes a long time. It almost seems impossible to write all the letters in under 2 minutes unless everyone is constantly writing.

1. that varies depending on your speed. If you think you can solve it within 10 min, go for it. We always go for the timed, however if you can't solve the timed at all then it might not be worth it. Generally all top teams will go for the timed.
I sorta remember last year's timed and yeah it was very long. However we manage to get around a 6 min solve at states, and I think teams can do better then that if given a similar timed due to another year of practice.

2. Practice practice and practice more. If you can't get a good start, memorizing more word patterns beforehand or looking at the freq table or just making a guess (knowing it can be wrong) can help.
We do the timed with all 3 ppl, and I find it to be a significant improvement, because we all are contributing to the solve. Space is always an issue but it gets better when you do more and more together. We kinda(?) have roles- one guy is constantly writing, while I tend to write more early on, but move more into a pointing out stuff role later on because I suck at filling in, while another guy scans the quote initially and writes more as I move into the pointing out stuff role.
Also just in general having a third person filling in even is useful, because filling in is hard lmao. But like practice. keep practicing. never stop practicing. and slowly your times should get better. the ability to solve aristos fast is probably the most important skill for doing well

[jimmy-bond]

I have two questions for the timed question:
1. When is a timed question too long and not worth everyone's time? In the two NY tests I have taken, the timed question has been very long. The regionals test had a E count around 20 but had a long hint similar to "Dear Johnny" or something. We did it in 6:40. In states, however, the E count was in the mid/high 20s and by the time we finished the cipher it was just after 10 minutes. It seems like no one else in the room was attempting it/smartly bailed out. Is there an approximate cutoff such as around 220+ letters where we shouldn't attempt it?

2. How do you work together to get faster on timed questions? Together, we can do timed anywhere from 4:30 to 7:30, but that isn't much faster than individually. How do we increase our efficiency together - should there be roles for each person? Right now we have 2 people writing because 3 gets hectic space wise. Our starts are sometimes slow and filling in letters always takes a long time. It almost seems impossible to write all the letters in under 2 minutes unless everyone is constantly writing.

1. Idk if this applies to everyone, but whenever I see a long timed problem, I can solve it much faster than if it were only one or two lines. I took a test with a timed question spanning two lines, and I was unable to solve it while my partner, who took the test separately, solved it in 9:56. So, to answer your question, I don't feel like there's a quote length at which you shouldn't try the timed question, but if you aren't confident in your abilities, maybe anything past 6 lines or so.

2. Similar to you, my team also has two people assigned to the timed problem. I agree that three is just a mess with so many hands, so the third person starts with Vigenere or Affine. Using this strategy, we solved the timed question at nats in a little over 3 minutes, and we don't necessarily have roles; we just look for the most common patterns and toss around potential words for the others. Getting sub-2 is extremely difficult and I'd imagine it comes with a LOT of practice, as Name mentioned. Unfortunately, my teammates and I are involved in many extracurriculars and can't coordinate meeting times, but it's certain that with an excruciating amount of practice, such times are possible.

[Name]

1. Idk if this applies to everyone, but whenever I see a long timed problem, I can solve it much faster than if it were only one or two lines. I took a test with a timed question spanning two lines, and I was unable to solve it while my partner, who took the test separately, solved it in 9:56. So, to answer your question, I don't feel like there's a quote length at which you shouldn't try the timed question, but if you aren't confident in your abilities, maybe anything past 6 lines or so.

2. Similar to you, my team also has two people assigned to the timed problem. I agree that three is just a mess with so many hands, so the third person starts with Vigenere or Affine. Using this strategy, we solved the timed question at nats in a little over 3 minutes, and we don't necessarily have roles; we just look for the most common patterns and toss around potential words for the others. Getting sub-2 is extremely difficult and I'd imagine it comes with a LOT of practice, as Name mentioned. Unfortunately, my teammates and I are involved in many extracurriculars and can't coordinate meeting times, but it's certain that with an excruciating amount of practice, such times are possible.

I think this really depends on the nature of the quote itself. Longer quotes give you more to start with while short ones have less to fill in. Short quotes with obvious start points are ideal for fast solves.

A semi consistent sub 2 min is prolly the benchmark for the very top teams (on a relatively easy 2-3 line timed. something like last year's nats timed or this year's wack MIT test would be nearly impossible to sub 2 min. 3 min on that nats is very impressive). Getting an occasional sub 2 is possible without too much practice, but consistently doing so does take extreme practice to marginally decrease your time. Most of this practice can be done individually, but it is vital to get practices in together.
(on a side note, I wonder if any team will hit sub 1 min at any comp w/o straight up recognizing the quote. I do think it is plausable)

For practicing obviously code tests are great but you can go through them very quickly. Often my partners and I write aristos for each other but my main source of practice is https://www.puzzlebaron.com
I think by now everyone knows about their cryptograms website (warning extremely addictive), but I found the autofill to kinda spoil you and for paper solves to be better for actually improving your time. Earlier this year I found their printable cryptos (which I think is sorta unknown) but is imo the single best source of practice with them releasing 8 printable cryptos every day.

[ET2020]

Does anyone know of some invitational tests that had an RSA question? The only one I've been able to find so far is Cornell.