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::collections::BTreeMap;

fn main() {
    let mut buf = String::new();
    let handle = std::io::stdin();
    handle.read_line(&mut buf).unwrap();
    let info: Vec<usize> = buf.trim().split_whitespace().map(|a| a.parse().unwrap()).collect();
    let n = info[0];
    let k = info[1];
    buf.clear();
    handle.read_line(&mut buf).unwrap();
    let mut ls: Vec<usize> = buf.trim().split_whitespace().map(|a| a.parse().unwrap()).collect();
    ls.sort();
    let mut total_len = 0;
    for l in ls.iter().rev().take(k) {
        total_len += *l;
    }
    println!("{}", total_len);
}