Answered step by step
Verified Expert Solution
Link Copied!

Question

1 Approved Answer

IN C i need 12 and 13 2. Write a program to help an analyst decrypt a simple substitution cipher. Your program should take the

IN C

i need 12 and 13

image text in transcribed

image text in transcribed

2. Write a program to help an analyst decrypt a simple substitution cipher. Your program should take the ciphertext as input, compute letter frequency counts, and display these for the analyst. The program should then allow the analyst to guess a key and display the results of the corresponding "decryption" with the putative key. 3. Extend the program described in Problem 12 so that it initially tries to decrypt the message. One sensible way to proceed is to use the computed letter frequencies and the known frequencies of English for an initial guess at the key. Then from the resulting putative decryption, count the number of dictionary words that appear and use this as a score. Next, for each letter in the key, try swapping it with the letter that is adjacent (with respect to frequency counts) and recompute the score. If the score improves, update the key; if not, don't change the putative key. Iterate this process until the score does not improve for an entire pass through the alphabet. At this point you will give your putative decryption to the analyst. To aid the analyst in the manual phase, your program must maintain all of the functionality of the program in Problem 12

Step by Step Solution

There are 3 Steps involved in it

Step: 1

blur-text-image

Get Instant Access to Expert-Tailored Solutions

See step-by-step solutions with expert insights and AI powered tools for academic success

Step: 2

blur-text-image

Step: 3

blur-text-image

Ace Your Homework with AI

Get the answers you need in no time with our AI-driven, step-by-step assistance

Get Started

Recommended Textbook for

Oracle 10g SQL

Authors: Joan Casteel, Lannes Morris Murphy

1st Edition

141883629X, 9781418836290

More Books

Students also viewed these Databases questions

Question

Which of the following processes has a negative S ?

Answered: 1 week ago