0172-Factorial-Trailing-Zeroes.py

'''
Given an integer n, return the number of trailing zeroes in n!.

Example 1:

Input: 3
Output: 0
Explanation: 3! = 6, no trailing zero.
Example 2:

Input: 5
Output: 1
Explanation: 5! = 120, one trailing zero.
Note: Your solution should be in logarithmic time complexity.
'''
class Solution:
    def trailingZeroes(self, n: int) -> int:
        
        res = 0
        
        while n:
            
            n //= 5
            res += n
            
        return res