#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vmi = vector<mint>;
using vvmi = vector<vmi>;
using vvvmi = vector<vvmi>;
#define all(a) (a).begin(), (a).end()
#define rep2(i, m, n) for (int i = (m); i < (n); ++i)
#define rep(i, n) rep2(i, 0, n)
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)

void solve(){
    
}
int op(int a, int b){
    return max(a, b);
}
int e(){return -1;}

int main(){
    int n, w; cin >> n >> w;
    vi vv(n), vw(n);
    rep(i, n)cin >> vv[i];
    rep(i, n)cin >> vw[i];
    //segtree<int, op, e> seg(n);
    //vector<segtree<int, op, e>> vs(w+1, seg);
    vvi dp(n, vi(w+1, -1));
    dp[n-1][0] = 0; dp[n-1][vw[n-1]] = vv[n-1];
    //vs[0].set(n-1, 0);
    //vs[vw[n-1]].set(n-1, vv[n-1]);
    drep(i, n-1){
        rep(j, w+1){
            /*int t = vs[j].get(i+1);
            vs[j].set(i, t);
            if(j - vw[i] < 0)continue;
            int p = vs[j-vw[i]].get(i+1);
            if(p == -1)continue;
            if(t < p + vv[i])vs[j].set(i, p + vv[i]);*/
            dp[i][j] = dp[i+1][j];
            if(j - vw[i] < 0)continue;
            if(dp[i+1][j - vw[i]] == -1)continue;
            dp[i][j] = max(dp[i][j], dp[i+1][j - vw[i]] + vv[i]);
        }
    }
    int tmp = 0;
    rep(i, w+1)tmp = max(tmp, dp[0][i]);
    int v = 0;
    int itr = 0;
    int now = 0;
    vi ans;
    while(v < tmp){
        bool ff = false;
        rep(j, w-now+1){
            if(dp[n-1][j] >= tmp-v){
                ans.push_back(n-1);
                ff = true;
                break;
            }
        }
        if(ff)break;
        int l = itr, r = n-1;
        int mid;
        while(r - l > 1){
            mid = (r+l)/2;
            bool f = false;
            rep(j, w-now+1){
                if(dp[mid][j] >= tmp-v){
                    f = true;
                    break;
                }
            }
            if(f){
                l = mid;
            }else{
                r = mid;
            }
        }
        ans.push_back(l);
        v += vv[l];
        now += vw[l];
        itr = l+1;
        if(itr >= n)break;
    }sort(all(ans));
    cout << ans.size() << endl;
    for(auto i : ans) cout << i+1 << " ";
    cout << endl;

    return 0;
}