import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) throws Exception{

        BufferedReader br= new BufferedReader(new InputStreamReader(System.in));
       String s[]=br.readLine().split(" ");
        int n=Integer.parseInt(s[0]);
        int k2=Integer.parseInt(s[1]);
        String c[]=br.readLine().split(" ");
        int dp[][]= new int[n][n];
        for(int l=1;l<=n;l++){
            for(int i=0;i<n-l+1;i++){
                int j = i+l-1;
                if(l==1){
                    dp[i][j]=Integer.parseInt(c[i]);
                }
                else{
                    dp[i][j] = Integer.MAX_VALUE;
                    for(int k=i;k<=j;k++){
                        if(k-i > k2 && j-k>k2){
                            dp[i][j]  = Math.min(dp[i][j] , dp[i][k-k2-1]+dp[k+k2+1][j] + Integer.parseInt(c[k]));
                        }
                        else if(k-i > k2){
                             dp[i][j]  = Math.min(dp[i][j] , dp[i][k-k2-1] + Integer.parseInt(c[k]));
                        }
                        else if(j-k>k2){
                            dp[i][j]  = Math.min(dp[i][j] , dp[k+k2+1][j] + Integer.parseInt(c[k]));
                        }
                        else{
                            dp[i][j]  = Math.min(dp[i][j] , Integer.parseInt(c[k]));
                        }
                    }
                }
            }
        }
      /*  for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                  System.out.print(dp[i][j]+" ");
            }
              System.out.println();
        }*/
        System.out.println(dp[0][n-1]);
    }
}