Question

LANGUAGE: PYTHON

A customized version of Polybius square will be introduced that would cover the English alphabet and basic punctuations. The original English adapted square is 5x5, however, this customized version is 8x8. [1] [2] [3] [4] [5] [6] [7] [8] C [1] # $ % & [2] ( ) [3] 0 1 2 3 4 5 6 7 141 | 8 9 TETTE A B C D E F I | J | K | L Ι Μ Ι Ν 171 T U V 181 X Y Z [ ] IN. HOIX

Write a function called: d_polybius(). The function applies the decryption scheme for the polybius cipher scheme above. The start of the function call the get_polybius_square function to get the square as a string.

The second scenario when the number of characters is not even, excluding ‘\n’. For instance: “71\n5” is an invalid cipher because there is no way that the last number correspond to a character (we need two numbers).

Answer 1

# if this editor loses indentation please check attached images.

def d_polybius(ciphertext,key=None):
i = 0
plaintext = ''
while(i<len(ciphertext)):
if ciphertext[i] != '\n':
rc = ciphertext[i:i+2]
if rc.isdigit():
rc = int(rc) #row col value
if rc<11 or rc >88:
print("Error")
return ''
else: # out of bonds of matrix
rc = str(rc)   
r = int(rc[0]) #getting r and c from rc
c = int(rc[1])
pos = (r-1)*8+c
ascii_val = pos+31 # in asci_val space( ) starts at 32 our
plaintext = plaintext+chr(ascii_val)# index start at 1 so adding 31 gives ascii value
i = i+2
else: # not a digit
print("Error")
return ''
else: #char is '\n'
plaintext=plaintext+ciphertext[i]
i = i+1
return plaintext
  
  
print(d_polybius("675258\n6552"))

10 9 def d_polybius(ciphertext,key=None): i = 0 plaintext = " while(i<len(ciphertext)): if ciphertext[i] != '\n': rc = ciphertext[i:i+2] if rc.isdigit(): rc = int(rc) #row col value if rc<11 or rc >88: print("Error") return " else: # out of bonds of matrix rc = str(rc) r = int(rc[@]) #getting r and c from ra c = int(rc[1]) pos= (r-1)*8+C ascii_val = pos+31 # in asci_val space() st. plaintext = plaintext+chr(ascii val)# index start at 1 so add i = i+2 else: # not a digit print("Error") return " else: #char is 'in'

c = int(rc[1]) pos = (r-1)*8+c ascii_val = pos+31 # in asci_val space() st plaintext = plaintext+chr(ascii_val)# index start at 1 so add, i = i+2 else: # not a digit print("Error") return " else: #char is 'in' plaintext=plaintext+ciphertext[i] i = i+1 return plaintext print(d_polybius("675258\n6552")) 40 input NAG ... Program finished with exit code o