import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] sa = br.readLine().split(" ");
		int a = Integer.parseInt(sa[0]);
		int b = Integer.parseInt(sa[1]);
		int c = Integer.parseInt(sa[2]);
		br.close();

		if (a <= b && b <= c || c <= b && b <= a) {
			System.out.println(0);
			return;
		}
		if (a <= b) {
			System.out.println(Math.min(b - a, b - c));
		} else {
			System.out.println(Math.min(a - b, c - b));
		}
	}
}