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)

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

fn main() {
    let (n, k) = {
        let mut buf = String::new();
        io::stdin().read_line(&mut buf).unwrap();
        let mut it = buf.split_whitespace();
        (
            i32::from_str(it.next().unwrap()).unwrap(),
            i32::from_str(it.next().unwrap()).unwrap(),
        )
    };
    let mut buf = String::new();
    io::stdin().read_line(&mut buf).unwrap();
    let mut p: Vec<i32> = buf.split_whitespace().map(|s| s.parse().unwrap()).collect();
    if n == 1 {
        println!("{}", p.get(0).unwrap());
        return
    }
    if n == k {
        let sum: i32 = p.iter().sum();
        println!("{}", sum);
        return
    }
    p.sort();
    let mut i = 0;
    let mut ans = 0;
    for a in p.iter() {
        if i >= k {
            println!("{}", ans);
            return
        }
        ans = ans + a;
        i = i + 1;
    }
}