using System;
using System.Collections.Generic;
using static System.Console;
namespace ConsoleApp
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] N = ReadLine().Split(' ');
            ulong A = ulong.Parse(N[0]);
            ulong B = ulong.Parse(N[1]);
            ulong C = ulong.Parse(N[2]);
            ulong count = 0;
            ulong ans = 0;
            ulong i = 0;
            ulong j = 0;
            
            if(A == 1 && B == 1 || B == 1)
            {
                WriteLine(C);
                return;
            }
            if(A == B && A == C && B == C)
            {
                WriteLine(C);
                return;
            }
            i = C / A;
            if(B * i == C && A == B)
            {
                ans += (i - 1) * 2;
                WriteLine(ans);
                return;
            }
            else if(B * i > C)
            {
                if(A + B == C)
                {
                    ans += i + A - 1;
                    WriteLine(ans);
                    return;
                }
                ans += i + A - 2;
                WriteLine(ans);
                return;
            }
            else if(B * i <= C)
            {
                if(A > B && B != 1)
                {
                    ans += i + A + (A - B);
                    WriteLine(ans);
                    return;
                }
                ans += i + A;
                WriteLine(ans);
                return;
            }
        }
    }
}