백준[ALGORITHM] - 팩토리얼 0의 개수 (1676)

n = int(input())
lst = list(range(n,0,-1))

temp = ''
count = 0

for i in range(len(lst)):
    temp = lst[-1] * lst[i-1]
    lst[-1] = temp
    temp = str(temp)

count = 0
for digit in reversed(str(temp)):
    if digit == '0':
        count += 1
    else:
        break
print(count)