#include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < int(n); i++)
#define rrep(i, n) for (int i = int(n) - 1; i >= 0; i--)
#define reps(i, n) for (int i = 1; i <= int(n); i++)
#define rreps(i, n) for (int i = int(n); i >= 1; i--)
#define repc(i, n) for (int i = 0; i <= int(n); i++)
#define rrepc(i, n) for (int i = int(n); i >= 0; i--)
#define repi(i, a, b) for (int i = int(a); i < int(b); i++)
#define repic(i, a, b) for (int i = int(a); i <= int(b); i++)
#define each(x, y) for (auto &x : y)
#define all(a) (a).begin(), (a).end()
#define bit(b) (1ll << (b))

using namespace std;

using i32 = int;
using i64 = long long;
using u64 = unsigned long long;
using f80 = long double;
using vi32 = vector<i32>;
using vi64 = vector<i64>;
using vu64 = vector<u64>;
using vf80 = vector<f80>;
using vstr = vector<string>;

inline void yes() { cout << "Yes" << '\n'; exit(0); }
inline void no() { cout << "No" << '\n'; exit(0); }
inline i64 gcd(i64 a, i64 b) { if (min(a, b) == 0) return max(a, b); if (a % b == 0) return b; return gcd(b, a % b); }
inline i64 lcm(i64 a, i64 b) { return a / gcd(a, b) * b; }
inline u64 xorshift() { static u64 x = 88172645463325252ull; x = x ^ (x << 7); return x = x ^ (x >> 9); }
template <typename T> class pqasc : public priority_queue<T, vector<T>, greater<T>> {};
template <typename T> class pqdesc : public priority_queue<T, vector<T>, less<T>> {};
template <typename T> inline void amax(T &x, T y) { if (x < y) x = y; }
template <typename T> inline void amin(T &x, T y) { if (x > y) x = y; }
template <typename T> inline T exp(T x, i64 n, T e = 1) { T r = e; while (n > 0) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; }
template <typename T> inline T bis(T ok, T ng, function<bool(T)> f, T eps = 1) { while (abs(ok - ng) > eps) { T mi = (ok + ng) / 2; (f(mi) ? ok : ng) = mi; } return ok; }
template <typename T> istream& operator>>(istream &is, vector<T> &v) { each(x, v) is >> x; return is; }
template <typename T> ostream& operator<<(ostream &os, vector<T> &v) { rep(i, v.size()) { if (i) os << ' '; os << v[i]; } return os; }
template <typename T, typename S> istream& operator>>(istream &is, pair<T, S> &p) { is >> p.first >> p.second; return is; }
template <typename T, typename S> ostream& operator<<(ostream &os, pair<T, S> &p) { os << p.first << ' ' << p.second; return os; }
void solve(); int main() { ios::sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(16); solve(); return 0; }

int dp[51][51][51][51];

void solve() {
  int n, c;
  cin >> n >> c;
  vi32 L(n), W(n);
  cin >> L >> W;
  rep(i, 51) rep(j, 51) rep(k, 51) rep(l, 51) dp[i][j][k][l] = -1;
  dp[0][0][0][0] = 0;
  rep(i, c) repc(j, 50) repc(k, 50) rep(l, c) rep(m, n) {
    if (dp[i][j][k][l] == -1) continue;
    if (l + W[m] > c) continue;
    
    if (j == 0 && k == 0) {
      amax(dp[i + 1][L[m]][0][l + W[m]], dp[i][j][k][l] + L[m]);
    } else if (j > 0 && k == 0 && j != L[m]) {
      amax(dp[i + 1][L[m]][j][l + W[m]], dp[i][j][k][l] + L[m]);
    } else if (j > 0 && k > 0) {
      if ((k > j && j < L[m] && k != L[m]) || (k < j && j > L[m] && k != L[m])) {
        amax(dp[i + 1][L[m]][j][l + W[m]], dp[i][j][k][l] + L[m]);
      }
    }
  }
  int ans = 0;
  repic(i, 3, c) reps(j, 50) reps(k, 50) repc(l, c) {
    amax(ans, dp[i][j][k][l]);
  }
  cout << ans << endl;
}