#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <set>
#include <map>

using namespace std;
typedef long long ll;

int N, C;
int L[50], W[50];

int dp[55][55][55][55];

const int INF = 52;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    cin >> N >> C;
    for(int i = 0; i < N; i++) cin >> L[i];
    for(int i = 0; i < N; i++) cin >> W[i];
    int ans = 0;
    for(int i = 0; i < N; i++){
        for(int j = 0; j < N; j++){
            if(W[i]+W[j] <= C && L[i] != L[j]) {
                dp[1][W[i]+W[j]][L[i]][L[j]] = max(dp[1][W[i]+W[j]][L[i]][L[j]], L[i]+L[j]);
                // cout << i << ' ' << j << ' ' << dp[1][W[i]+W[j]][L[j]][L[j]] << endl;
            }
        }
    }
    for(int i = 1; i <= C; i++){
        for(int j = 1; j <= C; j++){
            for(int k = 1; k <= 50; k++){
                for(int l = 1; l <= 50; l++){
                    if(k == l) continue;
                    for(int m = 0; m < N; m++){
                        if(k < l){
                            if(L[m] < l && L[m] != k && j+W[m] <= C && dp[i][j][k][l] != 0){
                                dp[i+1][j+W[m]][l][L[m]] = max(dp[i+1][j+W[m]][l][L[m]], dp[i][j][k][l]+L[m]);
                                ans = max(ans, dp[i+1][j+W[m]][l][L[m]]);
                            }
                        }else{
                            if(L[m] > l && L[m] != k && j+W[m] <= C && dp[i][j][k][l] != 0){
                                dp[i+1][j+W[m]][l][L[m]] = max(dp[i+1][j+W[m]][l][L[m]], dp[i][j][k][l]+L[m]);
                                ans = max(ans, dp[i+1][j+W[m]][l][L[m]]);
                            }
                        }
                    }
                }
            }
        }
    }
    cout << ans << endl;
}