N, K = map(int, input().split())
A = tuple(map(int, input().split()))
C = tuple(map(int, input().split()))
dp = [[dict() for _ in range(N)] for _ in range(N)]
ans = 0
for i in range(N):
    dp[i][i][C[i]] = A[i]
    ans = max(ans, dp[i][i][C[i]])

for k in range(N-1):
    for i in range(N):
        for c in dp[i][(i+k)%N]:
            if abs(c-C[(i+k+1)%N])<=K:
                if c not in dp[i][(i+k+1)%N]:
                    dp[i][(i+k+1)%N][c] = 0
                dp[i][(i+k+1)%N][c] = max(dp[i][(i+k+1)%N][c], dp[i][(i+k)%N][c]+A[(i+k+1)%N])
                ans = max(ans, dp[i][(i+k+1)%N][c])
                if C[(i+k+1)%N] not in dp[i][(i+k+1)%N]:
                    dp[i][(i+k+1)%N][C[(i+k+1)%N]] = 0
                dp[i][(i+k+1)%N][C[(i+k+1)%N]] = max(dp[i][(i+k+1)%N][C[(i+k+1)%N]], dp[i][(i+k)%N][c]+A[(i+k+1)%N])
                ans = max(ans, dp[i][(i+k+1)%N][C[(i+k+1)%N]])
            if abs(c-C[(i-1)%N])<=K:
                if c not in dp[(i-1)%N][(i+k)%N]:
                    dp[(i-1)%N][(i+k)%N][c] = 0
                dp[(i-1)%N][(i+k)%N][c] = max(dp[(i-1)%N][(i+k)%N][c], dp[i][(i+k)%N][c]+A[(i-1)%N])
                ans = max(ans, dp[(i-1)%N][(i+k)%N][c])
                if C[(i-1)%N] not in dp[(i-1)%N][(i+k)%N]:
                    dp[(i-1)%N][(i+k)%N][C[(i-1)%N]] = 0
                dp[(i-1)%N][(i+k)%N][C[(i-1)%N]] = max(dp[(i-1)%N][(i+k)%N][C[(i-1)%N]], dp[i][(i+k)%N][c]+A[(i-1)%N])
                ans = max(ans, dp[(i-1)%N][(i+k)%N][C[(i-1)%N]])


#print(dp)
print(ans)