import sys
from collections import defaultdict

def main():
    sys.setrecursionlimit(1 << 25)
    N, K = map(int, sys.stdin.readline().split())
    A = list(map(int, sys.stdin.readline().split()))
    C = list(map(int, sys.stdin.readline().split()))
    N = len(A)

    # 复制数组处理环
    A = A * 2
    C = C * 2

    max_len = N
    dp = [[defaultdict(int) for _ in range(2*N)] for _ in range(2*N)]

    # 初始化
    for i in range(2*N):
        dp[i][i][C[i]] = A[i]

    for length in range(2, max_len + 1):
        for l in range(2*N - length + 1):
            r = l + length - 1
            if r >= 2*N:
                break
            # 尝试拆分成两部分
            for mid in range(l, r):
                # 左边[l, mid]，右边[mid+1, r]
                # 检查是否有颜色对满足条件
                for c1 in dp[l][mid]:
                    for c2 in dp[mid+1][r]:
                        if abs(c1 - c2) <= K:
                            sum_val = dp[l][mid][c1] + dp[mid+1][r][c2]
                            # 可以选择任意颜色
                            for new_c in [c1, c2]:
                                if sum_val > dp[l][r][new_c]:
                                    dp[l][r][new_c] = sum_val

    # 处理环的情况，寻找最大值
    max_sum = 0
    for l in range(N):
        for r in range(l, l + N):
            if r >= 2*N:
                break
            current = dp[l][r]
            if current:
                for c in current:
                    if current[c] > max_sum:
                        max_sum = current[c]
    print(max_sum)

if __name__ == '__main__':
    main()