package main

import (
	"fmt"
	"sort"
)

func main() {
	var N, K int
	fmt.Scan(&N, &K)
	G := make([]int, N)
	for i := range G {
		fmt.Scan(&G[i])
	}
	sort.Ints(G)
	total := 0
	for i := (N - K); i < N; i++ {
		if G[i] > 0 {
		total = total + G[i]
		}
	}
	fmt.Println(total)
}