Problems
Number of zeroes in factorial
Number of zeroes in factorial
Find the number of zeros at the end of $n$! ($n$ factorial).
\InputFile
One integer $n~(1 \le n \le 2 \cdot 10^9)$.
\OutputFile
Print the number of zeros at the end of $n$!
Input example #1
7
Output example #1
1
Input example #2
12
Output example #2
2