Programming Exercise 3-1
Programming Exercise 9-3
# Part 1
# Encryption and decryption are inverse of one another
CODE = {‘A’:’)’,’a’:’0′,’B’:'(‘,’b’:’9′,’C’:’*’,’c’:’8′,\
‘D’:’&’,’d’:’7′,’E’:’^’,’e’:’6′,’F’:’%’,’f’:’5′,\
‘G’:’$’,’g’:’4′,’H’:’#’,’h’:’3′,’I’:’@’,’i’:’2′,\
‘J’:’!’,’j’:’1′,’K’:’Z’,’k’:’z’,’L’:’Y’,’l’:’y’,\
‘M’:’X’,’m’:’x’,’N’:’W’,’n’:’w’,’O’:’V’,’o’:’v’,\
‘P’:’U’,’p’:’u’,’Q’:’T’,’q’:’t’,’R’:’S’,’r’:’s’,\
‘S’:’R’,’s’:’r’,’T’:’Q’,’t’:’q’,’U’:’P’,’u’:’p’,\
‘V’:’O’,’v’:’o’,’W’:’N’,’w’:’n’,’X’:’M’,’x’:’m’,\
‘Y’:’L’,’y’:’l’,’Z’:’K’,’z’:’k’,’!’:’J’,’1′:’j’,\
‘@’:’I’,’2′:’i’,’#’:’H’,’3′:’h’,’$’:’G’,’4′:’g’,\
‘%’:’F’,’5′:’f’,’^’:’E’,’6′:’e’,’&’:’D’,’7′:’d’,\
‘*’:’C’,’8′:’c’,'(‘:’B’,’9′:’b’,’)’:’A’,’0′:’a’,\
‘:’:’,’,’,’:’:’,’?’:’.’,’.’:’?’,’<':'>‘,’>’:’<',\ "'":'"','"':"'",'+':'-','-':'+','=':';',';':'=',\ '{':'[','[':'{','}':']',']':'}'} def main(): # Obtain a string of the converted text. result = convert() # Open output file and write to it. output_name = input('Enter the name of the output file: ') output_file = open(output_name, 'w') output_file.write(result) output_file.close() # The convert function asks the user for a file name, opens # the file, and converts its contents using the CODE above. # It then returns a string of the converted text. def convert(): input_name = input('Enter the name of the input file: ') input_file = open(input_name, 'r') result = '' text = input_file.read() # If character is space, it is not converted; # otherwise convert. for ch in text: if ch.isspace(): result = result + ch else: result = result + CODE[ch] return result # Call the main function. main() # Part 2 # Encryption and decryption are inverse of one another CODE = {'A':')','a':'0','B':'(','b':'9','C':'*','c':'8',\ 'D':'&','d':'7','E':'^','e':'6','F':'%','f':'5',\ 'G':'$','g':'4','H':'#','h':'3','I':'@','i':'2',\ 'J':'!','j':'1','K':'Z','k':'z','L':'Y','l':'y',\ 'M':'X','m':'x','N':'W','n':'w','O':'V','o':'v',\ 'P':'U','p':'u','Q':'T','q':'t','R':'S','r':'s',\ 'S':'R','s':'r','T':'Q','t':'q','U':'P','u':'p',\ 'V':'O','v':'o','W':'N','w':'n','X':'M','x':'m',\ 'Y':'L','y':'l','Z':'K','z':'k','!':'J','1':'j',\ '@':'I','2':'i','#':'H','3':'h','$':'G','4':'g',\ '%':'F','5':'f','^':'E','6':'e','&':'D','7':'d',\ '*':'C','8':'c','(':'B','9':'b',')':'A','0':'a',\ ':':',',',':':','?':'.','.':'?','<':'>‘,’>’:’<',\ "'":'"','"':"'",'+':'-','-':'+','=':';',';':'=',\ '{':'[','[':'{','}':']',']':'}'} def main(): # Obtain a string of converted text. result = convert() # Write converted text to the screen. print(result) # The convert function asks the user for a file name, opens # the file, and converts its contents using the CODE above. # It then returns a string of the converted text. def convert(): input_name = input('Enter the name of the input file: ') input_file = open(input_name, 'r') result = '' text = input_file.read() # If character is space, it is not converted; # otherwise convert. for ch in text: if ch.isspace(): result = result + ch else: result = result + CODE[ch] return result # Call the main function. main()