N, K = map(int, input().split())
A = list(map(int, input().split()))

dpl = [[0] * (K + 1) for _ in range(N + 1)]
dpr = [[0] * (K + 1) for _ in range(N + 1)]
dpl[0][0] = dpr[N][0] = 1

for i in range(N):
    for j in range(K + 1):
        dpl[i + 1][j] = dpl[i][j]
    for j in range(0, K - A[i] + 1):
        if dpl[i][j]:
            dpl[i + 1][j + A[i]] = 1
for i in range(N - 1, -1, -1):
    for j in range(K + 1):
        dpr[i][j] = dpr[i + 1][j]
    for j in range(0, K - A[i] + 1):
        if dpr[i + 1][j]:
            dpr[i][j + A[i]] = 1
if not dpl[N][K]:
    print(-1)
else:
    ans = 0
    for i in range(N):
        not_use = 1
        for j in range(K + 1):
            if dpl[i][j] and dpr[i + 1][K - j]:
                not_use = 0
                break
        if not_use:
            ans += 1
    print(ans)