Python help, lists

[curtissmith003]

I am having trouble inputting data into a list with unknown amount. Also afterwards, I need to be able to then reprint the list in reverse while not using the reverse function.
Thank You

lengthOfList=(int(input(‘How many numbers do you want to list(1-10)?:’)))

myList=list(range(0,lengthOfList))

for INDEX in range (0,lengthOfList,1):
print(‘Enter number ‘, myList[INDEX]+1,’:’)

[Billfred]

Just a note: please make sure you’re adding posts to the right category (this is not the first one I’ve had to change from CD-Media -> Photos).

[dan]

@curtissmith003

I am having trouble

Could you please elaborate on that?

[Ankith]

If I’m understanding your question correctly I think you want to be able to add numbers to a list regardless of its size? Lists in python don’t have a fixed size so you can just initialize it like this:

list = []

and then add items to the list like this:

list.append(var)

[curtissmith003]

Thank you.

How do you input numbers for an unknown amount of times? I created the question “How many numbers do you want to enter?” The user can type in any number from 1-10. If the user types 3 for example, I need it to ask “Enter your first number:” Then “Enter your second number:” etc. I then want to use those numbers to come up with a sum, average, etc. So, I need each inputted number assigned a unique variable (I assume). I will not know ahead of time how many variables I will need. I am using the list function too [ ].

[connor.worley]

You are on the right track using range.

inputs = []
n = 3
for i in range(n):
    inputs.append(input(f'Enter input {i}: '))
print(inputs)

Try it and see what happens.

For fun, a one liner: inputs = list(map(lambda i: input(f'Enter input {i}: '), range(3)))

[jtrv]

@connor.worley

For fun, a one liner: inputs = list(map(lambda i: input(f'Enter input {i}: '), range(3)))

alternatively [input(f'Enter input {i}: ') for i in range(3)], but this probably isn’t immediately intuitive to a beginner

OP: I recommend Corey Schafer’s Python guides, as well as r/learnpython

[prensing]

Or just keep read numbers with “input()” until the user inputs a blank string:

while True:
    value = input("Enter a number (enter to quit): ")
    if not value.strip():
        break
    # rest of your code

[Brian_Maher]

@prensing

if not value.strip():

An equivalent and more intuitive line is if value.strip() == "":

[curtissmith003]

Thank you.
This is what my instructor replied:

myList = [ ]

then append to it in a loop that happens as many times as the user wants to

times = int(input(‘how many times’))

for i in range(0, times, 1 )

ask user to enter a value

myList.append( … ) # append the value to the list

Now I am more lost…

[connor.worley]

You already know how to ask the user for the number of inputs. Can you reuse that line of code to ask for the inputs themselves?

[auscompgeek]

Just a quick meta-question: this isn’t homework, is it? Some people don’t take kindly to (unknowingly) helping with homework, and the question sounds like something that might be set as homework.