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Python

Posted by Jamar Slade
Jamar Slade
2,480 Points

Collatz Sequence: Why would the code need to use print and return, I thought this was the same thing?

Write a function named collatz() that has one parameter named number. If the number is even, then collatz() should print number // 2 and return this value. If the number is odd, then collatz() should print and return 3 * number + 1. Then write a program that lets the user type in an integer and that keeps calling collatz() on that number until the function returns the value 

def collatz(number):

    if number % 2 == 0:
        print(number // 2)
        return number // 2

    elif number % 2 == 1:
        result = 3 * number + 1
        print(result)
        return result

n = input("Give me a number: ")

while n != 1:
    n = collatz(int(n))

1 Answer

Steven Parker
Steven Parker
243,266 Points
Steven Parker
Steven Parker
243,266 Points

Most exercise functions either print or return (but they are not the same thing).

This particular exercise is unusual in that the instructions clearly ask you to do both.