using System;
using System.Linq;
using System.Numerics;

namespace _0373
{
    class Program
    {
        static void Main(string[] args)
        {
            var s = Console.ReadLine().Split().Select(n => BigInteger.Parse(n)).ToArray();
            var a = s[0] * s[1] * s[2] % s[3];
            Console.WriteLine(a);
        }
    }
}