e-olymp
Problems

The ratio of product to the sum

The ratio of product to the sum

Find the ratio of the product of digits of natural number to their sum.

Input

One positive integer n, not greater than 2 ·109.

Output

The desired ratio, calculated with 3 decimal digits.

Time limit 1 second
Memory limit 128 MiB
Input example #1
36
Output example #1
2.000