#include <bits/stdc++.h>
using namespace std;
struct cww{cww(){ios::sync_with_stdio(false);cin.tie(0);}}star;
#define P(x) cout << (x) << endl
#define p(x) cout << (x)
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
#define rep(i,a,n) for(int i=(a), i##_len=(n); i<i##_len; ++i)
#define rrep(i,a,n) for(int i=(a); i>n; --i)
#define len(x) ((int)(x).size())
#define mp make_pair
#define eb emplace_back
typedef long long ll;
typedef vector<int> vi;
typedef vector<double> vd;
typedef vector<long long> vll;
typedef vector<string> vs;
typedef vector<bool> vb;
inline int f() {
	int a, b, s; cin >> a >> b >> s;
	int da = abs(s - a), db = abs(s - b);
	if(s == 1) return da + 1;
	if (da <= db) return da + s;
	int ans = db + s + abs(1 - a);
	return (a != 0) ? min(ans, db + da + a) : ans;
}
int main() {
	P(f());
	return 0;
}