#include <stdio.h>
#include <stdlib.h>

int compare(const void *a, const void *b)
{
	int *x = (int*)a;
	int *y = (int*)b;
	return *x - *y;
}

int main()
{
	int *num,n,t;
	int sum = 0;
	scanf("%d %d",&n,&t);
	num = (int*)malloc(sizeof(int) * n);
	int i;
	for(i=0;i<n;i++)
		scanf("%d",&num[i]);
	qsort(num,n,sizeof(int),compare);
	n -= 1;
	while(n >= 0){
		sum += num[n];
		n -= k;
	}
	printf("%d\n",sum);
	retunr 0;
}