#include <bits/stdc++.h>
#define show(x) std::cerr << #x << " = " << (x) << std::endl
using ll = long long;
using ld = long double;
constexpr ll MOD = 1000000007LL;
template <typename T>
constexpr T INF() { return std::numeric_limits<T>::max() / 16; }
std::mt19937 mt{std::random_device{}()};
template <typename T>
std::vector<T> Vec(const std::size_t n, T v) { return std::vector<T>(n, v); }
template <class... Args>
auto Vec(const std::size_t n, Args... args) { return std::vector<decltype(Vec(args...))>(n, Vec(args...)); }
template <typename T, typename A>
std::ostream& operator<<(std::ostream& os, const std::vector<T, A>& v)
{
    os << "[";
    for (const auto& p : v) { os << p << ","; }
    return (os << "]\n");
}
int main()
{
    int N, C;
    std::cin >> N >> C;
    std::vector<int> L(N), W(N);
    for (int i = 0; i < N; i++) { std::cin >> L[i]; }
    for (int i = 0; i < N; i++) { std::cin >> W[i]; }
    auto dp = Vec(N, N, 51, 0);
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            for (int k = 0; k < N; k++) {
                if (L[i] > L[j] and L[j] < L[k] and L[i] != L[k] and W[i] + W[j] + W[k] <= C) { dp[j][k][W[i] + W[j] + W[k]] = std::max(dp[j][k][W[i] + W[j] + W[k]], L[i] + L[j] + L[k]); }
                if (L[i] < L[j] and L[j] > L[k] and L[i] != L[k] and W[i] + W[j] + W[k] <= C) { dp[j][k][W[i] + W[j] + W[k]] = std::max(dp[j][k][W[i] + W[j] + W[k]], L[i] + L[j] + L[k]); }
            }
        }
    }
    for (int i = 0; i <= C; i++) {
        auto tmp = dp;
        for (int pp = 0; pp < N; pp++) {
            for (int p = 0; p < N; p++) {
                for (int c = 0; c <= C; c++) {
                    if (dp[pp][p][c] == 0) { continue; }
                    if (L[pp] > L[p]) {
                        for (int n = 0; n < N; n++) {
                            if (L[p] >= L[n] or L[pp] == L[n] or c + W[n] > C) { continue; }
                            tmp[p][n][c + W[n]] = std::max(tmp[p][n][c + W[n]], dp[pp][p][c] + L[n]);
                        }
                    } else if (L[pp] < L[p]) {
                        for (int n = 0; n < N; n++) {
                            if (L[p] <= L[n] or L[pp] == L[n] or c + W[n] > C) { continue; }
                            tmp[p][n][c + W[n]] = std::max(tmp[p][n][c + W[n]], dp[pp][p][c] + L[n]);
                        }
                    }
                }
            }
            dp = tmp;
        }
    }
    int ans = 0;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            for (int c = 0; c <= C; c++) { ans = std::max(ans, dp[i][j][c]); }
        }
    }
    std::cout << ans << std::endl;
    return 0;
}