<LeetCode><Easy> 172 Factorial Trailing Zeroes

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

Note: Your solution should be in logarithmic time complexity.

#Python2 44ms

class Solution(object):
def trailingZeroes(self, n):
"""
:type n: int
:rtype: int
"""
counts,delt=0,5
while 1:
increase=n/delt
if not increase:
return counts
counts+=increase
delt*=5


#Python2 递归 64ms

class Solution(object):
def trailingZeroes(self, n):
"""
:type n: int
:rtype: int
"""
getCounts=lambda n,delt=5:getCounts(n,delt*5)+n/delt if delt<=n else 0
return getCounts(n)