using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;
using System.Security.Cryptography;

class Program
{
    static int NN => int.Parse(ReadLine());
    static long[] NList => ReadLine().Split().Select(long.Parse).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var ans = c[2];
        if (c[0] <= c[2]) --ans;
        if (c[1] <= c[2]) --ans;
        WriteLine(ans);
    }
}