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

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, m, p, q) = (c[0], c[1], c[2], c[3]);
        var month = new int[12];
        for (var i = 0; i < 12; ++i) month[i] = m;
        for (var i = p - 1; i < p + q - 1; ++i) month[i] <<= 1;
        var sum = month.Sum();
        var year = n / sum;
        var rest = n % sum;
        for (var i = 0; i < 12; ++i)
        {
            rest -= month[i];
            if (rest <= 0)
            {
                WriteLine(year * 12 + i + 1);
                return;
            }
        }
    }
}