#include <stdio.h>
#include <algorithm>
#include <functional>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}

int main() {
	int n = ri();
	int k = ri();
	int a[n];
	for (auto &i : a) i = ri();
	std::sort(a, a + n, std::greater<>());
	int res = 0;
	for (int i = 0; i < k; i++) if (a[i] > 0) res += a[i];
	printf("%d\n", res);
	return 0;
}