Problem:
Score : 200 points

Problem Statement

Snuke has N sticks.
The length of the i-th stick is l_i.

Snuke is making a snake toy by joining K of the sticks together.

The length of the toy is represented by the sum of the individual sticks that compose it.
Find the maximum possible length of the toy.

Constraints

1 \leq K \leq N \leq 50

1 \leq l_i \leq 50

l_i is an integer.

Input

Input is given from Standard Input in the following format:

N K
l_1 l_2 l_3 ... l_{N}

Output

Print the answer.

Sample Input 1

5 3
1 2 3 4 5

Sample Output 1

12

You can make a toy of length 12 by joining the sticks of lengths 3, 4 and 5, which is the maximum possible length.

Sample Input 2

15 14
50 26 27 21 41 7 42 35 7 5 5 36 39 1 45

Sample Output 2

386

Solution in Java7 (OpenJDK 1.7.0) (judge verdict: Accepted)

import java.util.Scanner;

class Main{
	static void swap(int[] a,int idx1,int idx2){
		int t = a[idx1]; a[idx1] = a[idx2];  a[idx2] = t;
	}
	
	static void quicksort(int[] a,int left,int right){
		int pl = left;
		int pr = right;
		int x = a[(pl + pr) / 2];
		
		do{
			while(a[pl] < x) pl++;
			while(a[pr] > x) pr--;
			if(pl <= pr) swap(a,pl++,pr--);
		} while(pl <= pr);
		
		if(left < pr) quicksort(a,left,pr);
		if(pl < right) quicksort(a,pl,right);
	}
	
	public static void main(String[] args){
		Scanner std = new Scanner(System.in);
		
		int nx = std.nextInt();
		int[] x = new int[nx];
		int k = std.nextInt();
		int sum = 0;
		
		for(int i = 0;i < nx;i++){
			x[i] = std.nextInt();
		}
		
		quicksort(x,0,nx-1);
		
		for(int i = x.length - 1;i >= nx - k;i--){
			sum += x[i];
		}
		System.out.print(sum);
	}
}