n, k = map(int, input().split())
A = list(map(int, input().split()))
dp = [[False] * (k + 1) for _ in range(n + 1)]
dp[0][0] = True

for i, a in enumerate(A, 1):
    dp[i] = dp[i - 1].copy()
    for j in range(k, a - 1, -1):
        dp[i][j] |= dp[i - 1][j - a]

if not dp[n][k]:
    print(-1)
    exit()
    
dp2 = [[False] * (k + 1) for _ in range(n + 1)]
dp2[n][0] = True

for i in range(n - 1, -1, -1):
    a = A[i]
    dp2[i] = dp2[i + 1].copy()
    for j in range(k, a - 1, -1):
        dp2[i][j] |= dp2[i + 1][j - a]

ans = 0
for i, a in enumerate(A):
    plus = 1
    for j in range(k + 1):
        if dp[i][j] and dp2[i + 1][k - j]:
            plus = 0
            break
    ans += plus
print(ans)