n,C = map(int,input().split())
*v, = map(int,input().split())
*w, = map(int,input().split())

# dp[cost][2つ前][１つ前] = max(length)
N = 51
dp = [[[0]*N for _ in range(N)] for _ in range(C+1)]
for i in range(n):
    for j in range(n):
        if v[i] != v[j] and w[i]+w[j] <= C:
            dp[w[i]+w[j]][v[i]][v[j]] = v[i]+v[j]

ans = 0
for i in range(C):
    for j in range(N):
        for k in range(N):
            if dp[i][j][k] == 0: continue
            for l in range(n):
                if j == v[l]: continue
                if i+w[l] > C: continue
                if j > k < v[l] or j < k > v[l]:
                    x = dp[i][j][k] + v[l]
                    ans = max(ans,x)
                    dp[i+w[l]][k][v[l]] = max(dp[i+w[l]][k][v[l]], x)
print(ans)