CSC111 Lab 8 2015

--D. Thiebaut (talk) 14:10, 22 March 2015 (EDT)

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Part 1: While Loops

Exercise 1: Robust Input with While

def getPositiveNumber():
    #
    # put your code here
    #


def main():

    # Part 1, Exercise 1
    x = getPositiveNumber()
    print( "getPositiveNumber() returned", x )

main()

Complete the function getPositiveNumber() so that it asks the user for a number larger than 0, and keeps on prompting the user as long as she doesn't enter a valid number.

Below is an example of the interaction between computer and user.

Please enter a number greater than 0: -1
-1 is invalid.
Please enter a number greater than 0: -3
-3 is invalid.
Please enter a number greater than 0: 0
0 is invalid.
Please enter a number greater than 0: 20
getPositiveNumber() returned 20
>>>

Exercise 2: Ask for Yes/No answer

Same idea as in Exercise 1, but this time the new function, called getYesNo() will keep on asking a question until the user's input is "YES", "yes", "y", "NO", "no", or "n". Any combination of lower/upper case in the spelling is accepted ("yES" is valid).

Source

def getYesNo():
    #
    # put your code here
    #
            
def main():
    # Part1, Exercise 2
    likesChoco = getYesNo()
    if likesChoco in ["YES", "Y" ]:
        print( "Me too!" )
    else:
        print( "Sorry to hear that!" )
        
main()

Example output

Do you like chocolate (Y/N)? possibly
please enter by 'Yes' or 'No'

Do you like chocolate (Y/N)? I don't know
please enter by 'Yes' or 'No'

Do you like chocolate (Y/N)? Oui
please enter by 'Yes' or 'No'

Do you like chocolate (Y/N)? y
Me too!

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