How do I print the characters on the same line?

Question

I'm trying to print the cipher text on the same line. When I run the program now all the characters get printed on to the next line. How do I do this?

#!/usr/bin/env python3

import cs50
import sys

def main():

    if len(sys.argv) != 2:
        print('caesar.py k')
        exit(1)

    k = int(sys.argv[1])

    print('plaintext: ', end = '')

    s = cs50.get_string()

    print('ciphertext: ', end = '')

    for i in range(len(s)):

        c = s[i]

        if str.isupper(c):
            cipher = (((ord(c) - 65) + k) % 26) + 65
            print(chr(cipher))
        elif str.islower(c):
            cipher = (((ord(c)- 97) + k) % 26) + 97
            print(chr(cipher))
        else:
            print(chr(c))

    exit(0)


if __name__ == "__main__":
    main()

Answer 1

The error comes from

c - chr(65)

If you look at the type of chr(65) it's actually a string.

>>> type(chr(65))
str

The TypeError you're getting is just telling you that you can't subtract a string from another string.

You might want to look at using ord instead which returns an integer representing the Unicode code point of a character.

Furthermore

for i in range(len(s)):

    c = s[i]

Is a python anti-pattern and can be simplified wth just

for c in s:
    print(c)   # c is your character

Since s is an iterable

Answer 2

No worries, I answered this. I added a end = '' at the end of the print statements.

Answer 3

I think @Jack Evans is the best style to go. However, for your interest I've made some modifications to help answer your question (hopefully):

#!/usr/bin/env python3
import cs50
import sys

def main():

    if len(sys.argv) != 2:
        print('caesar.py k')
        exit(1)

    k = int(sys.argv[1])

    print('plaintext: ', end = '')
    s = cs50.get_string()
    print(s)

    print('ciphertext: ', end = '')

    for i in range(len(s)):

        c = s[i]

        if str.isupper(c):
            cipher = (((ord(c) - 65) + k) % 26) + 65
            print(chr(cipher), end= '')
        elif str.islower(c):
            cipher = (((ord(c)- 97) + k) % 26) + 97
            print(chr(cipher), end= '')
        else:
            print(chr(c), end= '')        
    print()
    exit(0)

if __name__ == "__main__":
    main()

Here is the example output if someone executed the script as:

./name_of_file 3

with the string being:

howdy

The result would be:

plaintext: howdy
ciphertext: krzgb

To answer you question directly, to have the print cipher characters print on the same line just change:

print(chr(cipher))

to

print(chr(cipher), end= '')

In Python, using print() without specifying how print should end it will automatically end with a newline. As you can see in the version I provided, you can use this idea to easily incorporate newlines.

Cheers