use std::io::Read;
use std::cmp::{max, min};

fn solve(a: usize, b: usize, c: usize) {
    let max_ac = max(a, c);
    let min_ac = min(a, c);
    if b > max_ac {
        println!("{}", min(b - max_ac, max_ac - min_ac));
    } else {
        println!("{}", min(min_ac - b, max_ac - min_ac));
    }
}

fn main() {
    let mut s = String::new();
    std::io::stdin().read_to_string(&mut s).ok();
    let s: Vec<usize> = s.trim().split('\n').next().unwrap().trim().split_whitespace()
        .map(|i| i.parse::<usize>().unwrap())
        .collect();
    solve(s[0], s[1], s[2]);
}