import java.util.Scanner;

public class No126 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int A = sc.nextInt();
		int B = sc.nextInt();
		int S = sc.nextInt();
		int l = 0; //距離
		if(S == 0) {
			System.out.println(0);
			return;
		}
		if(S == 1) {
			System.out.println(Math.abs(A-S) + S);
			return;
		}
		
		if(Math.abs(A-S) <= Math.abs(B-S)) {
			System.out.println(Math.abs(A-S) + S);
		}else if(Math.abs(S-1) <= Math.abs(S-A)) {
			System.out.println(Math.abs(S-B)+S-1+A);
		}
		else {
				System.out.println(Math.abs(A-B)+A);
		}
		
	}
}