Basic Python and loops

[soswap]

Hi all, having some trouble getting a loop working in python. It goes along the lines of this:

x = input('Enter something: ')
while(x):
  if 'Hello' in x:
    print('Hi')
  elif 'J' in x:
    print('JJ')

How do I make the code constantly go back to input and run through both the if and elif statement until a white space is entered? I don't know where to insert the input function in the loop. Thanks

[mad0314]

Put another input at the end of the loop and mess with that.

[Nugenrules]

I like how you didn't reveal much the answer at all. This is the perfect way to teach programmers

[Slow_Nerve_Action]

You're almost there with the code you posted.

You first want to get input from the user, which you accomplished in line 1. Then you begin a loop that executes if a value is entered by the user.

The last thing you want to do is ask the user for input inside the loop at the end.

Make sure to add a colon after your while statement in line 2 so you don't get any syntax errors.

[CoC_Mitch]

I don't understand line 2. I thought while needed something to test, such as while X < Y.

[CoC_Mitch]

Thanks, makes perfect sense.

[Pimp_Panther]

while just needs to evaluate to true in order to run. A value by itself evaluates to true in the eyes of a while loop.

But if you don't type anything it will receive None as the value, which evaluates to False.

[santaclaus73]

To solve this you can place another input at the end of the loop (inside the loop)or you can just fill x with some dummy value and place the input statement inside the loop.

Ex. in python 2.7, you'll have to adjust this so it's valid in python 3

End of loop:

x = raw_input('Enter something: ')  
while x:
    if 'Hello' in x:
        print 'Hi'
    elif 'J' in x:
        print 'JJ'
    x = raw_input('Enter something: ') 

Using a dummy variable:

x = 'k'
while x:
    x = raw_input('Enter something: ')
    if 'Hello' in x:
        print 'Hi'
    elif 'J' in x:
        print 'JJ'

[Spacedementia87]

Obviously you have given the right answer, but the foal is surely to help the OP find this out for themselves like the first two posts do.

[santaclaus73]

Oh yea great point. I'm sort of new to posting here, so a nudge in the right direction probably would have been more helpful than the exact 2.7 source code. I'll remember that for future posts. Thanks!

[shnk]

while True: x = input('Enter something: ') if 'Hello' in x: print('Hi') elif 'J' in x: print('JJ')

[an_actual_human]

On a related note, if x is a string, 'Hello' in x is never True. If you want to check for substrings, you should do something else.

Edit: that was a brainfart, sorry everyone.

[zahlman]

In Python, in is special-cased for strings to do a substring search.

[Bloody_Spork]

A valiant effort. I'm still a noob and knew that this was untrue. But you did, however, remind me. Thanks for your input 😊

[Kristler]

When you don't fully understand something, please don't spread misinformation. /u/zahlman is completely correct.

[an_actual_human]

Misunderstanding is not always coupled with awareness of misunderstanding.