/*
TASK:seq
LANG:C++
*/
#include <iostream>
using namespace std;
int k;
int n;
int a[1000001];
int sum=0;
int maxsum=0;
int sum_seq;

void seq(int time, int pos)
{
   if(time>k) return; 
   if(time==1) sum_seq=sum; 
   if(a[pos]!=a[pos-1] || pos==1)
   { 
      for(int i=pos; i<=n; i++)
      {
         sum_seq-=a[i];
         if(time==k)
         {
            maxsum+=sum_seq;
         }
         seq(time+1, i+1);
         sum_seq+=a[i];
      }
    }
    else seq(time, pos+1);      
}   

int main()
{
  cin >> n >> k;
  for(int i=1; i<=n; i++)
  {  
     cin >> a[i];
     sum+=a[i];
  }
 
  seq(1, 1);
  
  cout << maxsum << endl;
  return 0;
}
