The Challenge¶

Write a program that prints all the numbers up till the user-input defined value.
For multiples of three print “Fizz” instead of the number.
For multiples of five print “Buzz”.
For numbers which are multiples of both three and five print “FizzBuzz"

First Solution¶

"""This is the solution in its most basic form, allowing the upper number to be defined by user input"""
def fizzBuzz():
    x = int(input("Enter a number up to which you would like to 'FizzBuzz': "))
    nums = range(1,x+1)
    for n in nums:
        if n % 3 == 0 and n % 5 == 0:
            print "FizzBuzz",
        elif n % 3 == 0:
            print "Fizz",
        elif n % 5 == 0:
            print "Buzz",
        else:
            print n,

fizzBuzz()

Enter a number up to which you would like to 'FizzBuzz': 15
1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz

Great, but...

What is someone enters a negative number?

Dealing with negative numbers¶

"""Here I have added the absolute function to return a opsitive integer of whatever is input"""
def fizzBuzz():
    x = abs(int(input("Enter a number up to which you would like to 'FizzBuzz': ")))
    nums = range(1,x+1)
    for n in nums:
        if n % 3 == 0 and n % 5 == 0:
            print "FizzBuzz",
        elif n % 3 == 0:
            print "Fizz",
        elif n % 5 == 0:
            print "Buzz",
        else:
            print n,

fizzBuzz()

Enter a number up to which you would like to 'FizzBuzz': -15
1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz

Still going strong, but...

What if someone enters a number as a string (or any other string?)

Dealing with string inputs¶

"""With this change, the while statement will insist that a valid input is provided
    before the code will continue, and any name errors are handled with a bespoke message"""
def fizzBuzz():
    while True:
        try:
            x = abs(int(raw_input("Enter a number up to which you would like to 'FizzBuzz': ")))
            break
        except ValueError:
            print("Error! You must enter a number, for example: 6, 93, 529 etc.")
    nums = range(1,x+1)
    for n in nums:
        if n % 3 == 0 and n % 5 == 0:
            print "FizzBuzz",
        elif n % 3 == 0:
            print "Fizz",
        elif n % 5 == 0:
            print "Buzz",
        else:
            print n,

fizzBuzz()

Enter a number up to which you would like to 'FizzBuzz': Hello World!
Error! You must enter a number, for example: 6, 93, 529 etc.
Enter a number up to which you would like to 'FizzBuzz': 30
1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz 16 17 Fizz 19 Buzz Fizz 22 23 Fizz Buzz 26 Fizz 28 29 FizzBuzz

Okay, everything works as planned!

Ignoring the user input for readability, I will now look at other ways I could code the function to achieve the desired result.

"""All numbers divisible by 3 and 5 are divisible by 15
This is an interator generator so nothing is stored in memory"""
def fizzBuzz(numbers):
    for i in numbers:
        if i % 15 == 0:
            yield "FizzBuzz"
        elif i % 5 == 0:
            yield "Buzz"
        elif i % 3 == 0:
            yield "Fizz"
        else:
            yield str(i)
print " ".join(fizzBuzz(range(1,31)))

1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz 16 17 Fizz 19 Buzz Fizz 22 23 Fizz Buzz 26 Fizz 28 29 FizzBuzz

"""Here we append an empty string with either Fizz or Buzz or both when appropriate
    Then we return that string, unless it is empty, and then n is returned"""
for n in range(1, 31):
    s = ""
    if n % 3 == 0:
        s += "Fizz"
    if n % 5 == 0:
        s += "Buzz"
    print s or n,

1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz 16 17 Fizz 19 Buzz Fizz 22 23 Fizz Buzz 26 Fizz 28 29 FizzBuzz

"""This is essentially the same code as above, however I have now simplified it
    to avoid creating a variable to store the string inside each time a loop is run"""
for n in range(1, 31):
    print("Fizz"*(n % 3 == 0) + "Buzz"*(n % 5 == 0) or n),

1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz 16 17 Fizz 19 Buzz Fizz 22 23 Fizz Buzz 26 Fizz 28 29 FizzBuzz

This last solution seems to take up the least code, so I will combine this into the function:

def fizzBuzz():
    while True:
        try:
            x = abs(int(input("Enter a number up to which you would like to 'FizzBuzz': ")))
            break
        except NameError:
            print("Error! You must enter a numeric digit, for example: 6, 93, 529 etc.")
    nums = range(1,x+1)
    for n in range(1, 31):
        print("Fizz"*(n % 3 == 0) + "Buzz"*(n % 5 == 0) or n),

fizzBuzz()

Enter a number up to which you would like to 'FizzBuzz': Spam and Eggs
Error! You must enter a numeric digit, for example: 6, 93, 529 etc.
Enter a number up to which you would like to 'FizzBuzz': 30
1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz 16 17 Fizz 19 Buzz Fizz 22 23 Fizz Buzz 26 Fizz 28 29 FizzBuzz