#include <stdio.h>

int kado(int x, int y, int z) {
    if (x == y || x == z || y == z) return 0;
    return (x < y && y > z) || (x > y && y < z);
}

int N, C;
int L[50], W[50];
int dp[51][51][51];

void to(int *x, int y) {
    if (*x < y) *x = y;
}

int main(void) {
    scanf("%d %d", &N, &C);
    for (int i = 0; i < N; i++) {
        scanf("%d", L + i);
    }
    for (int i = 0; i < N; i++) {
        scanf("%d", W + i);
    }
    for (int i = 0; i <= C; i++) {
        for (int j = 1; j <= 50; j++) {
            for (int k = 1; k <= 50; k++) {
                dp[i][j][k] = -1e9;
            }
        }
    }
    int ans = 0;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            for (int k = 0; k < N; k++) {
                if (kado(L[i], L[j], L[k]) && W[i] + W[j] + W[k] <= C) {
                    to(&dp[W[i] + W[j] + W[k]][L[j]][L[k]], L[i] + L[j] + L[k]);
                }
            }
        }
    }
    for (int i = 1; i <= C; i++) {
        for (int j = 1; j <= 50; j++) {
            for (int k = 1; k <= 50; k++) {
                for (int l = 0; l < N; l++) {
                    if (kado(j, k, L[l]) && i + W[l] <= C) {
                        to(&dp[i + W[l]][k][L[l]], dp[i][j][k] + L[l]);
                    }
                }
            }
        }
    }
    for (int i = 1; i <= C; i++) {
        for (int j = 1; j <= 50; j++) {
            for (int k = 1; k <= 50; k++) {
                to(&ans, dp[i][j][k]);
            }
        }
    }
    printf("%d\n", ans);
    return 0;
}