import java.io.FileNotFoundException;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws FileNotFoundException {
		long t = System.currentTimeMillis();
		new Main().run();
		System.err.println(System.currentTimeMillis() - t);
	}
	
	void run() {
		Scanner sc = new Scanner(System.in);
		int A=sc.nextInt();
		int B=sc.nextInt();
		int S=sc.nextInt();
		if(Math.abs(S-A)<=Math.abs(S-B)) {
			System.out.println(Math.abs(S-A)+Math.abs(S-0));
		}else {
			if(A>0) {
				System.out.println(Math.abs(S-B)+Math.abs(A-B)+Math.abs(A));
			}else {
				System.out.println(Math.abs(S-B)+Math.abs(S-1)+2);
			}
		}
	}


	static void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}

}