Problem statement

https://binarysearch.com/problems/Collatz-Sequence/

Solution

We just need to simulate the process.

Complexity

Hopefully it is not big, O(m), where m is the length of sequence, but how long it is, is a good question.

Code

class Solution:
    def solve(self, n):
        ans = 0
        while n != 1:
            if n % 2 == 0:
                n = n//2
            else:
                n = 3*n + 1
            ans += 1
        return ans + 1