n,k = map(int,input().split())
A = list(map(int,input().split()))
A.sort()
cand = [[] for i in range(2)]
for ind in range(2):

    dp = [[-2]*(k+1) for i in range(n+1)]
    dp[0][0] = -1
    for i,a in enumerate(A):
        for j in range(k+1):
            if dp[i][j] == -2:
                continue
            dp[i+1][j] = max(dp[i+1][j],dp[i][j])
            if j+a <= k:
                dp[i+1][j+a] = i

    if dp[-1][k] == -2:
        print(-1)
        exit()

    now = k
    for i in range(n+1)[::-1]:
        cand[ind].append(dp[i][now])
        now -= A[dp[i][now]]
        if now == 0:
            break
    A = A[::-1]

s1 = set(cand[1])
s2 = set(cand[0])
print(len(s1 & s2))