Problem:
Score : 200 points

Problem Statement

Print all the integers that satisfies the following in ascending order:

Among the integers between A and B (inclusive), it is either within the K smallest integers or within the K largest integers.

Constraints

1 \leq A \leq B \leq 10^9

1 \leq K \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B K

Output

Print all the integers that satisfies the condition above in ascending order.

Sample Input 1

3 8 2

Sample Output 1

3
4
7
8

3 is the first smallest integer among the integers between 3 and 8.

4 is the second smallest integer among the integers between 3 and 8.

7 is the second largest integer among the integers between 3 and 8.

8 is the first largest integer among the integers between 3 and 8.

Sample Input 2

4 8 3

Sample Output 2

4
5
6
7
8

Sample Input 3

2 9 100

Sample Output 3

2
3
4
5
6
7
8
9

Solution in Rust (1.15.1) (judge verdict: Accepted)

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

#[allow(unused_macros)]
macro_rules! scan {
  ($e:expr; $t:ty) => {
    $e.get::<$t>()
  };
  ($e:expr; $($t:ty), *) => {
    ($($e.get::<$t>(),)*)
  };
  ($e:expr => $i:expr; $t:ty) => {
    (0..$i).map(|_| $e.get::<$t>()).collect::<Vec<$t>>()
  };
  ($e:expr => $row:expr, $col:expr; $t:ty) => {
    (0..$i).map(|_| scan!($e => $col; $t)).collect::<Vec<$t>>()
  }
}

struct Scanner<R: Read> {
  reader: R
}

#[allow(dead_code)]
impl<R: Read> Scanner<R> {
  fn new(reader: R) -> Scanner<R> {
    Scanner { reader: reader }
  }
  fn safe_get<T: FromStr>(&mut self) -> Option<T> {
    let token = self.reader.by_ref().bytes().map(|c| c.unwrap() as char)
      .skip_while(|c| c.is_whitespace())
      .take_while(|c| !c.is_whitespace())
      .collect::<String>();
    if token.is_empty() { None } else { token.parse().ok() }
  }
  fn get<T: FromStr>(&mut self) -> T {
    if let Some(v) = self.safe_get() { v } else {
      writeln!(stderr(), "Terminated with EOF").unwrap();
      std::process::exit(0);
    }
  }
}

trait Writable {
  fn write(&self, sep: &'static str) -> String;
}

impl<T: ToString> Writable for Vec<T> {
  fn write(&self, sep: &'static str) -> String {
    self.iter().map(|e| e.to_string()).collect::<Vec<String>>().join(sep)
  }
}

fn main() {
  let cin = stdin();
  let cin = cin.lock();
  let mut sc = Scanner::new(cin);
  let (a, b, k) = scan!(sc; usize, usize, usize);
  let mut vec = Vec::with_capacity(k * 2);
  if b - a + 1 < k {
    for i in a..(b + 1) {
      vec.push(i);
    }
  }
  else {
    for i in a..(a + k) {
      vec.push(i);
    }
    for i in (b - k + 1)..(b + 1) {
      vec.push(i);
    }
    vec.sort();
    vec.dedup();
  }
  println!("{}", vec.write("\n"));
}