using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
//using System.Text;
//using System.Text.RegularExpressions;
//using System.Globalization;
//using System.Diagnostics;
using static System.Console;
//using System.Numerics;
//using static System.Math;
//using pair = Pair<int, int>;

class Program
{
    static void Main()
    {
        //SetOut(new StreamWriter(OpenStandardOutput()) { AutoFlush = false });
        new Program().solve();
        Out.Flush();
    }
    readonly Scanner cin = new Scanner();
    readonly int[] dd = { 0, 1, 0, -1, 0 }; //→↓←↑
    readonly int mod = 1000000007;
    void chmax<T>(ref T a, T b) where T : IComparable<T> { a = a.CompareTo(b) < 0 ? b : a; }
    void chmin<T>(ref T a, T b) where T : IComparable<T> { a = a.CompareTo(b) < 0 ? a : b; }
    const int B = 50;

    void solve()
    {
        int N = cin.nextint;
        int C = cin.nextint;
        var L = cin.scanint;
        var W = cin.scanint;
        var dp = new int[C + 1][][];
        for (int i = 0; i < C + 1; i++)
        {
            dp[i] = new int[B + 1][];
            for (int j = 0; j < B + 1; j++)
            {
                dp[i][j] = new int[B + 1];
                for (int k = 0; k < B + 1; k++)
                {
                    dp[i][j][k] = int.MinValue;
                }
            }
        }

        //最初の3個
        for (int i = 0; i < N; i++)
        {
            for (int j = 0; j < N; j++)
            {
                if (i == j) continue;
                for (int k = 0; k < N; k++)
                {
                    if (i == k || j == k) continue;
                    int cost = W[i] + W[j] + W[k];
                    int len = L[i] + L[j] + L[k];

                    if (cost > C) continue;

                    if ((L[i] < L[j] && L[j] > L[k]) || (L[i] > L[j] && L[j] < L[k]))
                    {
                        chmax(ref dp[cost][L[j]][L[k]], len);
                    }
                }
            }
        }

        bool flag = true;
        while (flag)
        {
            flag = false;

            //rで更新したい
            for (int r = 0; r < N; r++)
            {
                int cost = W[r];
                int len = L[r];
                for (int i = 3; i <= C - cost; i++)
                {
                    for (int j = 1; j <= B; j++)//長さ
                    {
                        if (j == len) continue;
                        for (int k = 1; k <= B; k++)//長さ
                        {
                            if (dp[i][j][k] == int.MinValue) continue;
                            if((j < k && k > len) || (j > k && k < len))
                            {
                                if (dp[i + cost][k][len] < dp[i][j][k] + len)
                                {
                                    flag = true;
                                    dp[i + cost][k][len] = dp[i][j][k] + len;
                                }
                            }

                        }
                    }
                }
            }
        }

        int max = 0;
        foreach (var i in dp)
        {
            foreach (var j in i)
            {
                chmax(ref max, j.Max());
            }
        }
        WriteLine(max);


    }

}

class Scanner
{
    string[] s; int i;
    readonly char[] cs = new char[] { ' ' };
    public Scanner() { s = new string[0]; i = 0; }
    public string[] scan { get { return ReadLine().Split(); } }
    public int[] scanint { get { return Array.ConvertAll(scan, int.Parse); } }
    public long[] scanlong { get { return Array.ConvertAll(scan, long.Parse); } }
    public double[] scandouble { get { return Array.ConvertAll(scan, double.Parse); } }
    public string next
    {
        get
        {
            if (i < s.Length) return s[i++];
            string st = ReadLine();
            while (st == "") st = ReadLine();
            s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
            i = 0;
            return next;
        }
    }
    public int nextint { get { return int.Parse(next); } }
    public long nextlong { get { return long.Parse(next); } }
    public double nextdouble { get { return double.Parse(next); } }
    public void join<T>(IEnumerable<T> values) { WriteLine(string.Join(" ", values)); }
}