Codebusters C

TheWood
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Re: Codebusters C

Post by TheWood »

Sorry mb for not posting earlier.

Find the inverse of the following hill encryption key:
BRA
CEL
ETS
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Re: Codebusters C

Post by KITN1931 »

Can someone give me tips on solving patristocrats????
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Re: Codebusters C

Post by CongminhTran »

Hey guys,

I was just wondering if any of you guys could help me with the Hill Cipher, both decryption and encryption?

For encryption, how do you make an encryption matrix given plaintext- ciphertext letter pairs?

For decryption, how do you make a decryption matrix given plaintext-ciphertext letter pairs? Also, how do you decrypt when given a key and some ciphertext? Lastly, what if they ask you to produce a decryption matrix given only some plaintext (with number values all arranged in a matrix)? I was asking because at the Regionals test for my school, a couple of Hill Cipher questions where you had to produce A (the other one was THE) decryption matrix showed up, and we had no idea on how to do them.

If you guys could try to help, I would very much appreciate that!
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Re: Codebusters C

Post by jimmy-bond »

CongminhTran wrote:Hey guys,

I was just wondering if any of you guys could help me with the Hill Cipher, both decryption and encryption?

For encryption, how do you make an encryption matrix given plaintext- ciphertext letter pairs?

For decryption, how do you make a decryption matrix given plaintext-ciphertext letter pairs? Also, how do you decrypt when given a key and some ciphertext? Lastly, what if they ask you to produce a decryption matrix given only some plaintext (with number values all arranged in a matrix)? I was asking because at the Regionals test for my school, a couple of Hill Cipher questions where you had to produce A (the other one was THE) decryption matrix showed up, and we had no idea on how to do them.

If you guys could try to help, I would very much appreciate that!
KITN1931 wrote:Can someone give me tips on solving patristocrats????
These should go under the Code Busters thread under "Lab Events".
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Re: Codebusters C

Post by Name »

TheWood wrote:Sorry mb for not posting earlier.

Find the inverse of the following hill encryption key:
BRA
CEL
ETS
This year's rules doesn't cover inverting 3x3 hill keys.
However it should be
HUV
SIL
EDE
(I kinda stole this question, but I really liked the way they presented the Bacon cipher)
ADELE DEALT DEREK LAMPS DATED AS THE BLUNT CELLO DEALT FREED ACTORS GETS A DEATH FLYER EAGLE A YEAR YELLS OFTEN A ROAD
The first 4 letters in the ciphertext is "real"
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Re: Codebusters C

Post by dragonfruit35 »

Name wrote: (I kinda stole this question, but I really liked the way they presented the Bacon cipher)
ADELE DEALT DEREK LAMPS DATED AS THE BLUNT CELLO DEALT FREED ACTORS GETS A DEATH FLYER EAGLE A YEAR YELLS OFTEN A ROAD
The first 4 letters in the ciphertext is "real"

Hmmm... KINDA... :lol:
REALITY BEATS FANTASY
PS: I think you added an extra "S" at the end of ACTORS, because that makes six letters in the group.
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"it's not a pen, it's a principle!" - annie edison
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Re: Codebusters C

Post by Name »

dragonfruit35 wrote:
Name wrote: (I kinda stole this question, but I really liked the way they presented the Bacon cipher)
ADELE DEALT DEREK LAMPS DATED AS THE BLUNT CELLO DEALT FREED ACTORS GETS A DEATH FLYER EAGLE A YEAR YELLS OFTEN A ROAD
The first 4 letters in the ciphertext is "real"

Hmmm... KINDA... :lol:
REALITY BEATS FANTASY
PS: I think you added an extra "S" at the end of ACTORS, because that makes six letters in the group.
Yup and oops yeah I did.
South Woods MS, Syosset HS '21
BirdSO TD/ES
Past Events: Microbe, Invasive, Matsci, Fermi, Astro, Code, Fossils
1st place MIT Codebusters 2019-2020
1st place NYS Fermi Questions (2019), Astronomy and Codebusters (2021)
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Re: Codebusters C

Post by dragonfruit35 »

Decode this Vigenere-encrypted text where the five-letter key saved physicists from using Coulomb’s law infinitely for the rest of their lives.

zhy w-xoefv wwuudk felg atscvw g cifvacngj zhul ay ih klgtcu wwucdahrcme
The word “e-field” is part of the plaintext.
The key is GAUSS.
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virginia tech '24
2x codebusters national medalist

"it's not a pen, it's a principle!" - annie edison
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Re: Codebusters C

Post by starfruit »

the e-field equals zero inside a conductor that is in static equilibrium
code/forensics/it's about time
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dragonfruit35
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Re: Codebusters C

Post by dragonfruit35 »

starfruit wrote:the e-field equals zero inside a conductor that is in static equilibrium
Correct! Your turn.
tjhsst '20
virginia tech '24
2x codebusters national medalist

"it's not a pen, it's a principle!" - annie edison
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