#include < fstream >
using   namespace  std;

int  n,m;
int  s[ 16 ];
long   long  f[ 17 ][ 17 ];
int  main()
{
    ifstream cin( " bigexp.in " );
    ofstream cout( " bigexp.out " );
    cin >> n >> m;
     for ( int  i = 1 ;i <= m; ++ i)
         for ( int  j = 1 ;j <= n; ++ j)
            f[i][j] =- 0xFFFFFFF ;
    s[ 0 ] = 0 ;
     for ( int  i = 1 ;i <= n; ++ i){
        cin >> s[i];
        s[i] += s[i - 1 ];
        f[ 0 ][i] = s[i];
    }
     for ( int  k = 1 ;k <= m; ++ k)
         for ( int  i = k + 1 ;i <= n; ++ i)
             for ( int  j = i - 1 ;j >= k; -- j){
                 if (f[k][i] < f[k - 1 ][j] * (s[i] - s[j]))
                    f[k][i] = f[k - 1 ][j] * (s[i] - s[j]);
                 if (f[k][i] < f[k - 1 ][j] + (s[i] - s[j]))
                    f[k][i] = f[k - 1 ][j] + (s[i] - s[j]);
            }
    cout << f[m][n] << endl;
     return   0 ;
}