Concatenating user input?

Question

I want to concatenate user input with a ':' colon in-between.

My script is taking options through user input and I want to store it like:

Red:yellow:blue

I have created a loop to read user input, but not sure how to store it.

while True:
    color = input("please enter Color of your choice(To exit press No): ")
    if color == 'No':
        break
    color += color
print ("colors   ", color)

Possible duplicate of [Correct way to write line to file in Python](https://stackoverflow.com/questions/6159900/correct-way-to-write-line-to-file-in-python) — Roberto Anić Banić, Jun 19 '17 at 12:18

score 4 · Accepted Answer · answered Jun 19 '17 at 12:03

One simple approach to keep as close to your code as possible is to start off with an empty list called colors before entering your loop, and appending to that all the valid colors as you take inputs. Then, when you are done, you simply use the join method to take that list and make a string with the ':' separators.

colors = []
while True:
     color = input("please enter Color of your choice(To exit press No): ")
     if color == 'No':
       break
     else:
         colors.append(color)

colors = ':'.join(colors)
print ("colors   ", colors)

Demo:

please enter Color of your choice(To exit press No): red
please enter Color of your choice(To exit press No): blue
please enter Color of your choice(To exit press No): green
please enter Color of your choice(To exit press No): orange
please enter Color of your choice(To exit press No): No
colors    red:blue:green:orange

score 0 · Answer 2 · answered Jun 19 '17 at 11:58

0

You can concatenate a ':' after every input color

while True:
     color = input("please enter Color of your choice(To exit press No): ")
     if color == 'No':
       break
     color += color
     color += ':'
print ("colors   ", color)

answered Jun 19 '17 at 11:58

Akshay Apte

1,539
9
24

It will print the last color entered . – newbie Jun 19 '17 at 12:12

score 0 · Answer 3 · answered Jun 19 '17 at 11:58

0

you're looking for str.join(), to be used like so: ":".join(colors). Read more at https://docs.python.org/2/library/stdtypes.html#str.join

answered Jun 19 '17 at 11:58

Chitharanjan Das

1,283
10
15

That would require to give `join` an iterable. While providing the string would "work", it is not the correct iterable in this case. Based on providing a string, and calling join then you will end up with something like: `r:e:d`. Which is not the desired output. – idjaw Jun 19 '17 at 12:06

score 0 · Answer 4 · answered Jun 19 '17 at 12:07

0

Using a list is neat:

colors = []
while True:
    color = input("please enter Color of your choice(To exit press No): ")
    if color in ('No'):
        break
    colors.append(color)
print("colors   ", ':'.join(colors))

answered Jun 19 '17 at 12:07

rain_

734
1
13
24

1

Really? :) I guess you didn't notice the identical answer posted several minutes before this? – idjaw Jun 19 '17 at 12:10

Concatenating user input?

4 Answers4