#172. Factorial Trailing Zeroes
#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.

#https://www.youtube.com/watch?v=3Hdmv_Ym8PI&feature=youtu.be
class Solution:
    def trailingZeroes(self, n: int) -> int:
        out=0
        while n>=5:
            out+= n//5
            n=n//5
        return out