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Collatz Conjecture Formatting - Printable Version

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Collatz Conjecture Formatting - TreasureDragon - Feb-11-2019

Hi everyone,

So I figured out how to set up the technical aspect of the Collatz conjecture as well as making it print out the number of steps. However, I am required to print out everystep numerically ordered. So how do I attach a number in front to show which step it was? Here is an example of what we SHOULD have in total:

Enter a number : 22

1. 22 is even , divide in half : 11
2. 11 is odd , multiply by 3 and add 1: 34
3. 34 is even , divide in half : 17
4. 17 is odd , multiply by 3 and add 1: 52
5. 52 is even , divide in half : 26
6. 26 is even , divide in half : 13
7. 13 is odd , multiply by 3 and add 1: 40
8. 40 is even , divide in half : 20
9. 20 is even , divide in half : 10
10. 10 is even , divide in half : 5
11. 5 is odd , multiply by 3 and add 1: 16
12. 16 is even , divide in half : 8
13. 8 is even , divide in half : 4
14. 4 is even , divide in half : 2
15. 2 is even , divide in half : 1

Number of steps : 15
Largest number in sequence : 52

This is what I have that only calculates the process and states the number of steps:

number = int(input("Enter a number: "))
steps = 0

while number > 1: 
    if number % 2 == 0:
        number = number / 2
        steps += 1
    elif number % 2 == 1:
        number = number * 3 + 1
        steps += 1

print(f"\nNumber of steps: {steps}")
print(f"Largest number in sequence: {largest}")

Ok update: I figured out how to get the number to say what it is and the sequence but now I need help with ordering to see what the largest number was...


RE: Collatz Conjecture Formatting - ichabod801 - Feb-11-2019

Set max_num to number at the start of the loop. Each time through the loop, change max_num to number if number is higher than max_num (note: there's a really simple way to do this with the max function).


RE: Collatz Conjecture Formatting - TreasureDragon - Feb-11-2019

(Feb-11-2019, 10:34 PM)ichabod801 Wrote: Set max_num to number at the start of the loop. Each time through the loop, change max_num to number if number is higher than max_num (note: there's a really simple way to do this with the max function).

Oh I figured it out! Thank you for your help! :)