using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.Text.RegularExpressions;
using System.Linq;
using System.IO;

class Program
{
    static private Magatro M = new Magatro();
    static private void Main(string[]args)
    {
        M.Scan();
        M.Solve();
    }
}

public class Scanner
{
    private string[] S;
    private int Index;
    private char Separator;

    public Scanner(char separator = ' ')
    {
        Index = 0;
        Separator = separator;
    }

    private string[] Line()
    {
        return Console.ReadLine().Split(Separator);
    }

    public string Next()
    {
        string result;
        if (S == null || Index >= S.Length)
        {
            S = Line();
            Index = 0;
        }
        result = S[Index];
        Index++;
        return result;
    }
    public int NextInt()
    {
        return int.Parse(Next());
    }
    public double NextDouble()
    {
        return double.Parse(Next());
    }
    public long NextLong()
    {
        return long.Parse(Next());
    }
}

public class Magatro
{
    private int A, B, S;
    public void Scan()
    {
        Scanner sc = new Scanner();
        A = sc.NextInt();
        B = sc.NextInt();
        S = sc.NextInt();
    }
    public void Solve()
    {
        Console.WriteLine(Ans());
    }
    public int Ans()
    {
        int res = 0;
        if (Math.Abs(A - S) > Math.Abs(B - S))
        {
            if (A == 0)
            {
                if (S == 1)
                {
                    return 2;
                }
                else
                {
                    res += Math.Abs(B - S)+S-1;
                    return res + 2;
                }
            }
            else
            {
                res += Math.Abs(B - S);
                B = S;
                if (Math.Abs(B - 1) >= Math.Abs(A - B))
                {
                    res += Math.Abs(A - B);
                }
                else
                {
                    res += Math.Abs(B - 1);
                }
                return res + A;
            }
        }
        else
        {
            return Math.Abs(A - S) + S;
        }
    }
}