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;

fn main() -> io::Result<()>{
    let stdin = io::stdin();
    
    let (n,k) = {
	let mut buf = String::new();
	stdin.read_line(&mut buf)?;
	buf.retain(|c| c != '\n');
	let split = buf.split_ascii_whitespace();
	let tmp: Vec::<usize> = split.map(|c|  c.parse::<usize>().unwrap()).collect();
	(tmp[0],tmp[1])
    };

    let prices = {
	let mut buf = String::new();                                              
	stdin.read_line(&mut buf)?;                                                
	buf.retain(|c| c != '\n');                                                
	let split = buf.split_ascii_whitespace();                                 
	let mut tmp = split.map(|c| c.parse::<u64>().unwrap()).collect::<Vec::<u64>>();
	tmp.sort();
	tmp
    };

    println!("{:}",sum(&prices[..k]));

    Ok(())
}

fn sum(arr: &[u64]) -> u64{
    let mut res = 0;
    for ele in arr{
	res += *ele;
    }
    res
}