#include <bits/stdc++.h>

//const static double	de_PI	= 3.14159265358979323846;
//const static int	de_MOD	= 1000000007;
//const static int	de_MAX	= 999999999;
//const static int	de_MIN = -999999999;

int main(void) {

	//std::ifstream in("123.txt");	std::cin.rdbuf(in.rdbuf());

	int A = 0, B = 0, S = 0;
	std::cin >> A >> B >> S;

	if (S == 1) {
		std::cout << abs(A - S) + 1 << std::endl;
		return 0;
	}

	if (abs(A - S) <= abs(B - S)) {
		std::cout << abs(A - S) + S << std::endl;
		return 0;
	}

	if (abs(A - S) < (S - 1)) {
		std::cout << abs(B - S) + abs(A - S) + A << std::endl;
		return 0;
	}

	std::cout << abs(B - S) + S - 1 + abs(A - 1) + 1 << std::endl;
	return 0;

}