My code in java :- public static void main(String[] args) { InputReader in = new InputReader(System.in); int n=in.readInt(), k=in.readInt(), count=k;

    if(2*k>n){ k=n-k; count =k;}
   long ar[] = new long[n];
    for(int i=0; i<n; i++)
        ar[i]=in.readLong();
    Arrays.sort(ar);   //Array sorted
    long[] set1 = new long[k];
    long[] set2 = new long[n-k];
    int ptrl=n/2, ptrr=ptrl, sptr1=0, sptr2=0;
    set1[sptr1++]=ar[ptrl]; count--;
    ptrl-=2; ptrr+=2; 
    while(count>0){
        set2[sptr2++]=ar[ptrl+1];
        set2[sptr2++]=ar[ptrr-1];
        set1[sptr1++]=ar[ptrl];
        count--; ptrl-=2;
        if(count>0){
            set1[sptr1++]=ar[ptrr];
            count--;
        }
    }
    ptrl++;
    while(ptrl>=0){
        set2[sptr2++]=ar[ptrl];
        ptrl--;
    }
    int p=n-1;
    while(sptr2!=(n-k)){
        set2[sptr2++]=ar[p];
        p--;
    }
    //calculate diff
    long ans=0;
    for(int i=0; i<k; i++){
        for(int j=0; j<(n-k); j++){
            ans+=(long)Math.abs(set1[i]-set2[j]);
        }
    }
    System.out.print(ans);
}