#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;
typedef unsigned long long ull;

int main(){
  int N, C;
  cin >> N >> C;
  vector<int> L, W;
  rep(i,N){
    int l;
    cin >> l;
    L.push_back(l);
  }
  rep(i,N){
    int w;
    cin >> w;
    W.push_back(w);
  }

  map<vector<int>,int> m;
  rep(i,N){
    rep(j,N){
      if(L[i] == L[j]) continue;
      m[{L[i],L[j],W[i]+W[j]}] = L[i] + L[j];
    }
  }

  int ret = 0;
  while(true){
    map<vector<int>,int> t;
    for(auto& e : m){
      const vector<int>& v = e.first;
      rep(i,N){
        if(v[0] < v[1]){
          if(v[1] > L[i] && v[0] != L[i]){
            int c = v[2] + W[i];
            int l = e.second + L[i];
            if(c <= C){
              vector<int> tmp = {v[1],L[i],c};
              if(t[tmp] < l){
                t[tmp] = l;
                ret = max(ret, l);
              }
            }
          }
        }else{
          if(v[1] < L[i] && v[0] != L[i]){
            int c = v[2] + W[i];
            int l = e.second + L[i];
            if(c <= C){
              vector<int> tmp = {v[1],L[i],c};
              if(t[tmp] < l){
                t[tmp] = l;
                ret = max(ret, l);
              }
            }
          }
        }
      }
    }
    if(t.size() == 0) break;
    swap(t, m);
  }

  cout << ret << endl;
  
  return 0;
}