#include <iostream>
#include <cstdio>
#include <string>
#include <sstream>
#include <algorithm>
#include <math.h>
#include <map>
#include <iomanip>
#include <vector>
#include <queue>
#include <set>
#define PI 3.14159265359
#define INF 99999999;
#define rep(i, n) for(int i=0; i<n; i++)
#define REP(n) rep(i, n)
#define EPS 1e-10
typedef long long ll;
using namespace std;



/*
class Target
{
public:
	vector <string> draw(int n)
	{

	}
};
*/



int main()
{
	int A, B, S;
	int absAS, absBS;
	int ans = 0;
	
	cin >> A >> B >> S;
	absAS = abs(A - S);
	absBS = abs(B - S);
	if (S == 1)
	{
		ans += absAS;
		ans += 1;
	} else if (absAS < absBS) {
		ans += absAS;
		ans += S;
	} else if (absAS > absBS) {
		ans += absBS;
		ans += absAS;
		ans += A;
		ans += 1;
	} else if (absAS == absBS) {
		ans += absAS;
		ans += S;
	}
	
	cout << ans << endl;
	
	return 0;
}