Projects 1 (Chapter 1 Frequency Analysis):

The ciphertext below was encrypted using a substitution cipher. In your favorite language (in C++ or Python) decrypt the ciphertext without knowledge of the key using frequency analysis

lrvmnir bpr sumvbwvr jx bpr lmiwv yjeryrkbi jx qmbm wi

bpr xjvni mkd ymibrut jx irhx wi bpr riirkvr jx

ymbinlmtmipw utn qmumbr dj w ipmhh but bj rhnvwdmbr bpr

yjeryrkbi jx bpr qmbm mvvjudwko bj yt wkbrusurbmbwjk

lmird jk xjubt trmui jx ibndt

wb wi kjb mk rmit bmiq bj rashmwk rmvp yjeryrkb mkd wbi

iwokwxwvmkvr mkd ijyr ynib urymwk nkrashmwkrd bj ower m

vjyshrbr rashmkmbwjk jkr cjnhd pmer bj lr fnmhwxwrd mkd

wkiswurd bj invp mk rabrkb bpmb pr vjnhd urmvp bpr ibmbr

jx rkhwopbrkrd ywkd vmsmlhr jx urvjokwgwko ijnkdhrii

ijnkd mkd ipmsrhrii ipmsr w dj kjb drry ytirhx bpr xwkmh

mnbpjuwbt lnb yt rasruwrkvr cwbp qmbm pmi hrxb kj djnlb

bpmb bpr xjhhjcwko wi bpr sujsru msshwvmbwjk mkd

wkbrusurbmbwjk w jxxru yt bprjuwri wk bpr pjsr bpmb bpr

riirkvr jx jqwkmcmk qmumbr cwhh urymwk wkbmvb

a) Frequency analysis: write a program in C++ or python to compute the relative frequency of all letters A...Z in the ciphertext given above.

b) In order to decrypt the ciphertext look at the table 1.1 below, “Frequency” column and substitute the letters with more closer number which you obtained in part a. Note that the text is relatively short and that the letter frequencies in it might not perfectly align with that of general English language from the table. Try to substitute letters represented its letter frequencies and then try to read the text you obtained and make changes. Please write detail report what you did in each step.