A11146. Round Subset

Let's call the roundness of the number the number of zeros to which it ends.

You have an array of $n$ numbers. You need to choose a subset of exactly $k$ numbers so that the roundness of the product of the selected numbers will be maximum possible.

The first line contains two integer numbers $n$ and $k$ ( $1<=n<=200,1<=k<=n$ ).

The second line contains $n$ space-separated integer numbers $a_{1},a_{2},...,a_{n}$ ( $1<=a_{i}<=10^{18}$ ).

Print maximal roundness of product of the chosen subset of length $k$ .

In the first example there are 3 subsets of 2 numbers. $[50,4]$ has product 200 with roundness 2, $[4,20]$ — product 80, roundness 1, $[50,20]$ — product 1000, roundness 3.

In the second example subset $[15,16,25]$ has product 6000, roundness 3.

In the third example all subsets has product with roundness 0.