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.
Input
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 a1, a2, ..., an (1 ≤ ai ≤ 1018).
Output
Print maximal roundness of product of the chosen subset of length k.
Examples
Note
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.
#include<algorithm>
#include<iostream>
#include<string>
#include<map>//int dx[4]={0,0,-1,1};int dy[4]={-1,1,0,0};
#include<set>//int gcd(int a,int b){return b?gcd(b,a%b):a;}
#include<vector>
#include<cmath>
#include<stack>
#include<string.h>
#include<stdlib.h>
#include<cstdio>
#define maxn 220
#define UB (maxn*64)
#define ll __int64
#define INF 10000000
using namespace std;
const int inf =0x3f3f3f3f;
int n,k;
ll seq[maxn];
int c2[maxn],c5[maxn];
ll dp[maxn][UB];
/*
题目大意:给定n个数要求选恰好k个数,,
要求求出其乘积尾零最多的个数。
刚开始没看到k的限制,,
潇洒的写出了二维dp(可压缩),,
尾零取决于2和5因子的个数的最小值,,
所以可把每个数拆成2和5的个数的二元组,,
对于这个二元组序列采用背包做法。。
*/
int main()
{
//scanf("%d%d",&n,&k);
cin>>n>>k;
for(int i=0;i<n;i++)
{
cin>>seq[i];
///scanf("%I64d",&seq[i]);
while(seq[i]%2==0)
{
seq[i]/=2;
c2[i]++;
}
while(seq[i]%5==0)
{
seq[i]/=5;
c5[i]++;
}
}
memset(dp,-inf,sizeof(dp));
dp[0][0]=0;
for(int i=0;i<n;i++)
{
for(int j=k;j>=1;j--)
for(int p=c2[i];p<UB;p++)
{
///ll tp=dp[j-1][p-c2[i]];
// if(tp==-1) continue;
dp[j][p] = max( dp[j][p] , dp[j-1][p-c2[i]]+c5[i] );
}
/*
cout<<i<<"次"<<endl;
for(int j=1;j<=k;j++)
{
for(int p=0;p<=UB;p++)
cout<<dp[j][p]<<" ";
cout<<endl;
}*/
}
ll ans=0;
for(ll i=0;i<UB;i++)
{
///if(dp[k][i]==-1) continue;
ans=max(ans,min(dp[k][i],i));
}
cout<<ans<<endl;
//printf("%I64d\n",ans);
return 0;
}