Code mẫu

def main():
    n, k = map(int, input().split())
    c = list(map(int, input().split()))
    d = list(map(int, input().split()))

    group = [[] for i in range(3)]
    for i in range(n):
        group[d[i] % 3].append(c[i])

    for i in range(3):
        group[i].sort()
        group[i].extend([k + 1] * 3)

    ans = 0
    for m0 in range(3):
        for m1 in range(3):
            m2 = m1
            if len(group[0]) < m0 or len(group[1]) < m1 or len(group[2]) < m2: 
                continue
            cost = sum(group[0][:m0]) + sum(group[1][:m1]) + sum(group[2][:m2])
            p = [m0, m1, m2]
            if cost > k:
                continue
            while cost <= k:
                mx_val = min((sum(group[i][p[i]:p[i] + 3]), i) for i in range(3))
                cost += mx_val[0]
                p[mx_val[1]] += 3
            ans = max(ans, sum(p) - 3)

    print(ans)

main()