#define _USE_MATH_DEFINES
#include <algorithm>
#include <cstdio>
#include <functional>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;
typedef pair<ll, int> ll_i;
typedef pair<double, int> d_i;
typedef pair<ll, ll> ll_ll;
typedef pair<double, double> d_d;
struct edge { int u, v, w; };

ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;
int INF = INT_MAX / 2;

int main() {
	int A, B, S;
	cin >> A >> B >> S;
	if (S == 1) {
		if (A == 0) cout << 2 << endl;
		else cout << A << endl;
	}
	else {
		if (abs(A - S) <= abs(B - S))
			cout << abs(A - S) + S << endl;
		else if (A == 0)
			cout << abs(B - S) + S + 2 << endl;
		else
			cout << abs(B - S) + abs(A - B) + A << endl;
	}
}