using System;
using System.Collections.Generic;
using System.Linq;

// No.3329 Only the Rightest Choice is Right!!!
// https://yukicoder.me/problems/no/3329
class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("4 5");
            WillReturn.Add("1 4 2 3");
            WillReturn.Add("1 4 2 3");
            //2
            //3 4
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("6 3000");
            WillReturn.Add("1 1 1 1 1 1");
            WillReturn.Add("3000 3000 3000 3000 3000 3000");
            //1
            //6
        }
        else if (InputPattern == "Input3") {
            WillReturn.Add("10 3000");
            WillReturn.Add("2992 3000 1 1 1 1 1 1 1 1");
            WillReturn.Add("2992 3000 1 1 1 1 1 1 1 1");
            //1
            //2
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static long[] GetSplitArr(string pStr)
    {
        return (pStr == "" ? new string[0] : pStr.Split(' ')).Select(pX => long.Parse(pX)).ToArray();
    }

    struct ItemInfoDef
    {
        internal long Score;
        internal long Weight;
    }
    static ItemInfoDef[] mItemInfoArr;

    static void Main()
    {
        List<string> InputList = GetInputList();
        long[] wkArr = GetSplitArr(InputList[0]);
        long WeightLimit = wkArr[1];

        long[] ValueArr = GetSplitArr(InputList[1]);
        long[] WeightArr = GetSplitArr(InputList[2]);

        var ItemInfoList = new List<ItemInfoDef>();
        for (long I = 0; I <= ValueArr.GetUpperBound(0); I++) {
            ItemInfoDef WillAdd;
            WillAdd.Score = ValueArr[I];
            WillAdd.Weight = WeightArr[I];
            ItemInfoList.Add(WillAdd);
        }
        mItemInfoArr = ItemInfoList.ToArray();
        long UB = mItemInfoArr.GetUpperBound(0);

        var DPDictArr = new Dictionary<long, JyoutaiDef>[UB + 1];

        for (long I = UB; 0 <= I; I--) {
            if (I < UB) {
                DPDictArr[I] = new Dictionary<long, JyoutaiDef>(DPDictArr[I + 1]);
            }
            else {
                DPDictArr[I] = new Dictionary<long, JyoutaiDef>();
            }

            Action<long, long> UpdateAct = (pNewScore, pWeightSum) =>
            {
                if (pWeightSum > WeightLimit) return;

                bool IsOK = false;
                if (DPDictArr[I].ContainsKey(pWeightSum)) {
                    if (DPDictArr[I][pWeightSum].Score < pNewScore) {
                        IsOK = true;
                    }
                    else if (DPDictArr[I][pWeightSum].Score == pNewScore) {
                        if (DPDictArr[I][pWeightSum].LastItemInd < I) {
                            IsOK = true;
                        }
                    }
                }
                else {
                    IsOK = true;
                }

                if (IsOK) {
                    JyoutaiDef NewJyoutai;
                    NewJyoutai.Score = pNewScore;
                    NewJyoutai.LastItemInd = I;
                    DPDictArr[I][pWeightSum] = NewJyoutai;
                }
            };

            if (I < UB) {
                foreach (var EachPair in DPDictArr[I + 1]) {
                    UpdateAct(EachPair.Value.Score + mItemInfoArr[I].Score, EachPair.Key + mItemInfoArr[I].Weight);
                }
            }

            UpdateAct(mItemInfoArr[I].Score, mItemInfoArr[I].Weight);
        }

        //for (long I = UB; 0 <= I; I--) {
        //    Console.WriteLine("■■■{0}までのDB結果■■■", I);
        //    foreach (var EachPair in DPDictArr[I]) {
        //        Console.WriteLine("重さ={0},Score={1},LastItemInd={2}",
        //            EachPair.Key, EachPair.Value.Score, EachPair.Value.LastItemInd);
        //    }
        //}

        ExecDP(DPDictArr, WeightLimit);
    }

    // DP復元を行う
    static void ExecDP(Dictionary<long, JyoutaiDef>[] pDPDictArr, long pWeightLimit)
    {
        long UB = pDPDictArr.GetUpperBound(0);

        var AnswerIndList = new List<long>();

        long CurrInd = 0;
        long CurrWeightLimit = pWeightLimit;

        while (true) {
            if (CurrInd > UB) break;

            var CurrDict = pDPDictArr[CurrInd];
            var Tmp1 = CurrDict.Where(pX => pX.Key <= CurrWeightLimit);
            var Tmp2 = Tmp1.OrderByDescending(pX => pX.Value.Score);
            var Tmp3 = Tmp2.ThenByDescending(pX => pX.Value.LastItemInd);
            if (Tmp3.Any() == false) break;
            JyoutaiDef CurrAnswer = Tmp3.First().Value;

            AnswerIndList.Add(CurrAnswer.LastItemInd);
            CurrWeightLimit -= mItemInfoArr[CurrAnswer.LastItemInd].Weight;
            CurrInd = CurrAnswer.LastItemInd + 1;
        }
        Console.WriteLine(AnswerIndList.Count);

        for (int I = 0; I <= AnswerIndList.Count - 1; I++) {
            // 1オリジンに変更
            AnswerIndList[I]++;
        }

        Console.WriteLine(LongEnumJoin(" ", AnswerIndList));
    }

    struct JyoutaiDef
    {
        internal long Score;
        internal long LastItemInd;
    }

    // セパレータとLong型の列挙を引数として、結合したstringを返す
    static string LongEnumJoin(string pSeparater, IEnumerable<long> pEnum)
    {
        string[] StrArr = Array.ConvertAll(pEnum.ToArray(), pX => pX.ToString());
        return string.Join(pSeparater, StrArr);
    }
}