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Python The Solution: While Loops

Enes artun
PLUS
Enes artun
Courses Plus Student 2,364 Points
Posted by Enes artun
Enes artun
Courses Plus Student 2,364 Points

Problem 2 with list comprehension. How can I do it?

Hi. I am trying to do solve problem 2 with list comprehension but I am failing. I want to turn the list into integers because I am getting 'unsupported operand type(s) for -: 'str' and 'int' error on line print('Total is: ', sum(numbers)). How can I fix it?

def total_and_average():
    numbers = []

    while True:
      for int(ask) for ask in numbers:
        ask = input('Please type a number. Type q to exit.  ')
        numbers.append(ask)


        if ask == 'q':
          print('Exitting. Here are the list, sum and avarage of the numbers:')
          print(numbers)
          print('Total is :  ', sum(numbers))
          average = sum(numbers)/len(numbers)
          print(round(average))
        elif ask.isalpha() == True:
          print('Please type a number.')
          break

1 Answer

Steven Parker
Steven Parker
231,198 Points
Steven Parker
Steven Parker
231,198 Points

I see a few issues:

  • you don't need the "for" loop, you're already in a "while" loop
  • append to the numbers list only after checking for "q" or a letter (with an "else:" clause)
  • convert the string you get from "input" into a number as you add it (numbers.append(int(ask)))
  • there seems to be a mix of 2 and 4 spaces for indentation - pick one and use it consistently