Codebusters C

TheWood
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Re: Codebusters C

Postby TheWood » February 28th, 2019, 4:42 pm

Sorry mb for not posting earlier.

Find the inverse of the following hill encryption key:
BRA
CEL
ETS
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KITN1931
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Re: Codebusters C

Postby KITN1931 » March 1st, 2019, 3:54 pm

Can someone give me tips on solving patristocrats????

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Re: Codebusters C

Postby CongminhTran » March 1st, 2019, 7:08 pm

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

Postby jimmy-bond » March 1st, 2019, 7:20 pm

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!
Can someone give me tips on solving patristocrats????
These should go under the Code Busters thread under "Lab Events".
If life gives you melons, you're dyslexic.

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Code Busters(16), DD(40), FQ(39), Forensics(36), WQ(27)
CriB(26), DP (11), FF(1), MM(14), P&P(6)
CriB(36), DD(35), FF(2), MM(20)

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Re: Codebusters C

Postby Name » March 12th, 2019, 10:26 pm

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"
South Woods MS/Syosset HS '21
Favorite Past Events: Microbe, Invasive, Matsci, Fermi
Events!: Astro, Code, Fossils
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dragonfruit35
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Re: Codebusters C

Postby dragonfruit35 » March 14th, 2019, 8:07 pm

(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.

2019 (Duke/Reg/Cornell/States/Nats)
Mission 3/7/- Sounds 4/2/- Herp -/-/11/1/26 MV 2/3/7/3/10 Code 3/1/1/1/5
2020 (CMU/Reg/SOUP?/States?/Nats?)
GV ?/? Detector ?/? Code ?/?

Goooooooo Colonials!!!

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Re: Codebusters C

Postby Name » March 14th, 2019, 8:37 pm

(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
Favorite Past Events: Microbe, Invasive, Matsci, Fermi
Events!: Astro, Code, Fossils
Div C medals: 29

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dragonfruit35
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Re: Codebusters C

Postby dragonfruit35 » March 15th, 2019, 11:28 am

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.

2019 (Duke/Reg/Cornell/States/Nats)
Mission 3/7/- Sounds 4/2/- Herp -/-/11/1/26 MV 2/3/7/3/10 Code 3/1/1/1/5
2020 (CMU/Reg/SOUP?/States?/Nats?)
GV ?/? Detector ?/? Code ?/?

Goooooooo Colonials!!!

starfruit
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Re: Codebusters C

Postby starfruit » March 16th, 2019, 7:02 pm

the e-field equals zero inside a conductor that is in static equilibrium
2020 events - we'll seeeeee

fhs&aet '23

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dragonfruit35
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Re: Codebusters C

Postby dragonfruit35 » March 17th, 2019, 7:19 am

the e-field equals zero inside a conductor that is in static equilibrium
Correct! Your turn.

2019 (Duke/Reg/Cornell/States/Nats)
Mission 3/7/- Sounds 4/2/- Herp -/-/11/1/26 MV 2/3/7/3/10 Code 3/1/1/1/5
2020 (CMU/Reg/SOUP?/States?/Nats?)
GV ?/? Detector ?/? Code ?/?

Goooooooo Colonials!!!


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