#define _USE_MATH_DEFINES
#include  <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
#include<math.h>
#include<iomanip>
#include<stdio.h>
#include <stdlib.h>
#include<stdio.h>
#include <queue>
#include<map>
#include <sstream>
#include<set>
#include<stack>

//#include<bits/stdc++.h>


using namespace std;



int main() {
	
	int a, b, s;
	cin >> a >> b >> s;

	int x = 0, y = 0;

	x = abs(s - a) ;
	x += s;

	y = abs(s - b) ;
	if (!a) {
		a++; y++;
	}
	y += abs(s - a) ;
	y += a;

	cout << min(x, y) << endl;

	return 0;


		
}