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 Rust (1.15.1) (judge verdict: Accepted)

use std::io::stdin;
use std::str::FromStr;

fn read_2taple<T: FromStr>() -> (T, T) {
    let mut buf = String::new();
    stdin().read_line(&mut buf).unwrap();
    let mut iter = buf
        .trim()
        .split_whitespace()
        .map(|x| x.parse().ok().unwrap());
    (iter.next().unwrap(), iter.next().unwrap())
}

fn read_vec<T: FromStr>() -> Vec<T> {
    let mut buf = String::new();
    stdin().read_line(&mut buf).unwrap();
    buf.trim()
        .split_whitespace()
        .map(|x| x.parse().ok().unwrap())
        .collect()
}

use std::collections::BinaryHeap;
fn main() {
    let (_n, k) = read_2taple::<u32>();
    let l: Vec<u32> = read_vec();
    let mut heap = BinaryHeap::from(l);
    let ans = (0..k).fold(0, |ans, _| ans + heap.pop().unwrap());
    println!("{}", ans);
}