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

class Program
{
    static long NN => long.Parse(ReadLine());
    static long[] NList => ReadLine().Split().Select(long.Parse).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var ok = 1_000_000_000_000_000_000;
        var ng = 0L;
        while (ok - ng > 1)
        {
            var mid = (ok + ng) / 2;
            var bd = mid / c[0];
            var ad = mid - bd;
            var bdsum = bd * c[1];
            if (bd != 0 && (bdsum < bd || bdsum < c[1] || bdsum % c[1] != 0)) ok = mid;
            else if (ad + bdsum >= c[2]) ok = mid;
            else ng = mid;
        }
        WriteLine(ok);
    }
}