Problem:
Score : 200 points

Problem Statement

A shop sells N kinds of fruits, Fruit 1, \ldots, N, at prices of p_1, \ldots, p_N yen per item, respectively. (Yen is the currency of Japan.)

Here, we will choose K kinds of fruits and buy one of each chosen kind. Find the minimum possible total price of those fruits.

Constraints

1 \leq K \leq N \leq 1000

1 \leq p_i \leq 1000

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N K
p_1 p_2 \ldots p_N

Output

Print an integer representing the minimum possible total price of fruits.

Sample Input 1

5 3
50 100 80 120 80

Sample Output 1

210

This shop sells Fruit 1, 2, 3, 4, and 5 for 50 yen, 100 yen, 80 yen, 120 yen, and 80 yen, respectively.

The minimum total price for three kinds of fruits is 50 + 80 + 80 = 210 yen when choosing Fruit 1, 3, and 5.

Sample Input 2

1 1
1000

Sample Output 2

1000

Solution in Rust (1.42.0) (judge verdict: Accepted)

#![allow(unused_imports)]
#![allow(dead_code)]
use datastructure::*;
use grapth::*;
use input_scanner::*;
use math::*;
use string_algorithm::*;
use util::*;

use std::cmp;
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, LinkedList, VecDeque};

fn main() {
    let mut scan = Scanner::new();
    let n: usize = scan.next();
    let k: usize = scan.next();
    let mut p: Vec<i32> = scan.next_vec(n);
    p.sort();
    let mut ans = 0;
    for i in 0..k {
        ans += p[i];
    }
    println!("{}", ans);
}

mod datastructure {}
mod grapth {}
mod math {}
mod string_algorithm {}
mod util {}
mod input_scanner {
    pub struct Scanner {
        bytes: Vec<u8>,
        begin: usize,
        end: usize,
    }

    impl Scanner {
        pub fn new() -> Self {
            use std::io::Read;
            let mut buffer: Vec<u8> = Vec::new();
            std::io::stdin().read_to_end(&mut buffer).unwrap();
            let end = (0..buffer.len())
                .find(|i| buffer[*i].is_ascii_whitespace())
                .unwrap_or(buffer.len());
            Scanner {
                bytes: buffer,
                begin: 0,
                end: end,
            }
        }
        pub fn next<T: std::str::FromStr>(&mut self) -> T {
            let s: &str =
                unsafe { std::str::from_utf8_unchecked(&self.bytes[self.begin..self.end]) };
            let ret: T = s.parse::<T>().ok().expect("Parse error.");
            self.skip();
            ret
        }
        pub fn next_vec<T: std::str::FromStr>(&mut self, n: usize) -> Vec<T> {
            (0..n).map(|_| self.next()).collect()
        }
        pub fn next_word(&mut self) -> Vec<u8> {
            let r = Vec::from(&self.bytes[self.begin..self.end]);
            self.skip();
            r
        }
        fn skip(&mut self) {
            self.begin = (self.end..self.bytes.len())
                .find(|i| !self.bytes[*i].is_ascii_whitespace())
                .unwrap_or(self.bytes.len());
            self.end = (self.begin..self.bytes.len())
                .find(|i| self.bytes[*i].is_ascii_whitespace())
                .unwrap_or(self.bytes.len());
        }
    }
}