using System;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] inputA = Console.ReadLine().Split(' ');
            long X = long.Parse(inputA[0]);
            long Y = long.Parse(inputA[1]);
            long Z = long.Parse(inputA[2]);
            long count = 0;
            if (X<=Z&&Y<=Z)
            {
                count = Z - 2;
            }else if(X<=Z||Y<=Z)
            {
                count = Z - 1;
            }
            else
            {
                count = Z;
            }
            Console.WriteLine(count);
        }
    }
}