Question

Write a script in python that inputs a line of plaintext and a distance value and outputs an encrypted text using a Caesar cipher. The script should work for any printable characters.

Answer 1

NOTE: The code i have written will encrypt every printable character including space, special symbol etc.


Code:

def main():
        # fetching plaintext as input
        line = input('Enter a plaintext: ')
        # taking the distance value
        dist = int(input('Enter the shift value: '))

        enc_char = ''   
        # iterating through each character in line
        for char in line:
                # if char is an alphabet
                if char.isalpha():
                        num = ord(char)
                        num += dist

                        # if char is a lowercase                        
                        if char.islower():
                                if num > ord('z'):
                                        num -= 26
                                elif num < ord('a'):
                                        num += 26

                        # if char is an uppercase
                        elif char.isupper():
                                if num > ord('Z'):
                                        num -= 26
                                elif num < ord('A'):
                                        num += 26

                        enc_char += chr(num)            

                # if char is not an alphabet and it is some digit or special character
                else:
                        num = ord(char)
                        num += dist
                        # assuming ascii characters are upto 127 characters
                        # if the char crossed this 127 we will rotate it
                        if num > 127:
                                num -= 127
                        enc_char += chr(num)

        print('The encrypted text is: ', enc_char)

if __name__=='__main__':
        main()

Sample Output: