Calculate the number of trailing zeros in n! Write a function which takes n as a parameter, and returns the number of trailing zeros in n!.

Input Constraints

0 &lt;= n &lt;= 10^100

Output Constraints

Should be return the result in less than 10 seconds.

Test Input

1
213
45678
1234567
78943533
4567894123
121233112233112231233112323123


Test Output

0
51
11416
308638
19735878
1141973522
30308278058278057808278080759


Shortest code by character count wins.
Python 50 47 Characters
 
n=input()
x=5
s=0
while n/x:s+=n/x;x*=5
print s