n,k = map(int,input().split())
a = list(map(int,input().split()))
max_k = k+1
dp = [set() for _ in range(max_k)]
dp[0].add(0)

for i in range(n):
    aa = a[i]
    n_dp =  [set() for _ in range(max_k)]
    for j in range(max_k):
        if n_dp[j]:
            pass
#             p = set()
#             for x in dp[j]:
#                 if x in n_dp[j]:
#                     p.add(x)
#             n_dp[j] = p
        else:
            for x in dp[j]:
                n_dp[j].add(x)
            
        if dp[j]:
            if aa + j <= k:
                if dp[aa + j]:
                    p = set()
                    for x in dp[aa + j]:
                        if x in dp[j]:
                            p.add(x)
                    n_dp[aa + j] = p
                else:
                    n_dp[aa+j].add(i+1)
                    for x in dp[j]:
                        n_dp[aa+j].add(x)
    dp = n_dp
#     print(dp)
if dp[-1]:
    print(len(dp[-1])-1)
else:
    print(-1)