leetcode/numberOfSteps.py at master · Kymoraa/leetcode · GitHub

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"""
Given an integer num, return the number of steps to reduce it to zero.
In one step, if the current number is even, you have to divide it by 2, otherwise, you have to subtract 1 from it.


Example 1:
Input: num = 14
Output: 6
Explanation:
Step 1) 14 is even; divide by 2 and obtain 7.
Step 2) 7 is odd; subtract 1 and obtain 6.
Step 3) 6 is even; divide by 2 and obtain 3.
Step 4) 3 is odd; subtract 1 and obtain 2.
Step 5) 2 is even; divide by 2 and obtain 1.
Step 6) 1 is odd; subtract 1 and obtain 0.


Runtime: 44 ms, faster than 51.03% of Python3 online submissions for Number of Steps to Reduce a Number to Zero.
Memory Usage: 13.8 MB, less than 64.53% of Python3 online submissions for Number of Steps to Reduce a Number to Zero.
"""


class Solution:
    def numberOfSteps(self, num: int) -> int:
        count = 0
        while num != 0:
            if num % 2 == 0:
                num /= 2
                count += 1
            else:
                num -= 1
                count += 1
        return count