CS377: Database Design - Iteration in Python (3 Points)

Developed by Professor Tralie and Professor Mongan.

Exercise Goals

The goals of this exercise are:

1. To use iteration to compute a discrete value
2. To use conditionals to make choices during each loop iteration

Modify the ThreeXPlusOne.py file to solve the 3x+1 problem using a loop and conditional.

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Netid

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ThreeXPlusOne.py

def threeXPlusOne(x): # TODO - solve the 3x+1 problem here # while x is not 1, set x to half of itself if val is even, and to 3x+1 if it is odd # count and return the number of iterations you needed until x became 1

main.py

ans1 = threeXPlusOne(5) ans2 = threeXPlusOne(27) ans3 = threeXPlusOne(17) print(str(ans1) + "-" + str(ans2) + "-" + str(ans3))

Output

Trivia

This problem is part of the Collatz Conjecture which suggests that any value will eventually converge back to 1 after a finite number of iterations. We don’t know if this is true!