using System;

public class Hello
{
    public static void Main()
    {
        string[] line = Console.ReadLine().Trim().Split(' ');
        var a = long.Parse(line[0]);
        var b = long.Parse(line[1]);
        var c = long.Parse(line[2]);
        var res = getAns(a, b, c);
        Console.WriteLine(res);
    }
    public static long getAns(long a, long b, long c)
    {
        if ( c == 1) return 1;
        if (a == 1 && b >= c) return 1;
        var ng = 0L; var ok = 1000000000000000001L;
        while (ok - ng > 1)
        {
            var mid = ng + (ok - ng) / 2;
            if (check(a, b, c, mid)) ok = mid;
            else ng = mid;
        }
        return ok;
    }
    public static bool check(long a, long b, long c, long t)
    {
        var w1 = t / a;
        var w2 = w1 * b + t - w1;
        return w2 >= c;
    }
}