CODEWITHSUNDEEP
pythonpython-3.xinput
D. Shin
D. Shin

Reputation: 335

Better way for taking multiple inputs with a for loop?

I would like to use a for loop to get inputs for many questions I have to receive. I managed to make some code, but it seems there should be a better way. Maybe I can reduce the number of variables I'm using?

## <Desired Result>
## onset : 3mo
## location : earth
## character : red

checks = ['onset','location','character']
l1 = ['onset','location','character']
l2 = ['onset','location','character']

for i in range(len(checks)):
    l2[i] = input(checks[i])

for i in range(len(checks)):
    print(l1[i]+" : "+l2[i])

Upvotes: 1

Views: 150

Answers (4)

Tomerikoo
Tomerikoo

Reputation: 19403

A few observations on your code:

  1. Note that you never actually change l1 so basically it is unnecessary and wherever you use l1 replace with checks.

  2. It is not necessary to define l2 this way as you are overriding all its values anyway, so you could just define l2 = [] and then use append in your loop:

    for i in range(len(checks)):
    l2.append(input(checks[i]))

  3. Both your loops have exactly the same range, so you could combine them to 1:

    for i in range(len(checks)):
    l2[i] = input(checks[i])
    print(l1[i]+" : "+l2[i])

Now, using list-comprehension and the join method of strings, you could actually reduce this code to 3 lines (and get rid of l1):

checks = ['onset', 'location', 'character']

l2 = [input(x) for x in checks]

print("\n".join(checks[i]+" : "+l2[i] for i in range(len(checks))))

Or more neatly using zip:

print("\n".join(check + " : " + ans for check, ans in zip(checks, l2)))

Lastly, to reduce even one more line (and get rid of l2):

checks = ['onset', 'location', 'character']

print("\n".join(check + " : " + input(check) for check in checks))

We could also avoid using join and use the chance to further reduce to one line (getting rid of checks) using print's extra arguments and list-unpacking:

print(*(check + " : " + input(check) for check in ['onset', 'location', 'character']), sep='\n')

Upvotes: 3

Ed Ward
Ed Ward

Reputation: 2331

For a truly 1-line solution to your for-loops, you could do your list comprehension like this:

l2 = [(n, print(l1[i]+" : "+n))[0] for i, n in enumerate([input(x + ": ") for x in checks])]

Ouput:

onseta
locationb
characterc
onset : a
location : b
character : c

EDIT

As others mentioned, this is not best practice, so use something like this:

checks = ['onset','location','character']

l2 = [input(f"Check {n}:\n > ") for n in checks]

print(*(f"{j}: {l2[i]}\n" for i, j in enumerate(checks)), sep="")

Output:

Check onset:
 > ok
Check location:
 > ok
Check character:
 > ok
onset: ok
location: ok
character: ok

Upvotes: 0

ngShravil.py
ngShravil.py

Reputation: 5048

You should not initialize the list of desired length and take input for each element. You can use append method to that.

The following code will help you:

checks = ['onset','location','character']
arr = []
for i in checks:
    arr.append(input(i + ' : '))

If you want to reduce the number of lines, you can try the following:

arr = [ input(i + ' : ') for i in ['onset','location','character']]

Upvotes: 0

shuberman
shuberman

Reputation: 1490

What you are trying to achieve for is done using List comprehensions.

In your case you can do that in a single line.

l2 = [input(x) for x in checks]

Upvotes: 0

Related Questions