mod = 1000000007
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

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

    dp = [[0] * (K+1) for _ in range(N+1)]
    dp[0][0] = 1
    for i, a in enumerate(A):
        for k in range(K + 1):
            dp[i + 1][k] = (dp[i + 1][k] + dp[i][k])%mod
            if k + a <= K:
                dp[i + 1][k + a] = (dp[i + 1][k + a] + dp[i][k])%mod

    if dp[-1][-1] == 0:
        print(-1)
    else:
        dp2 = [[0] * (K + 1) for _ in range(N + 1)]
        dp2[0][0] = 1
        for i, a in enumerate(A[::-1]):
            for k in range(K + 1):
                dp2[i + 1][k] = (dp2[i + 1][k] + dp2[i][k]) % mod
                if k + a <= K:
                    dp2[i + 1][k + a] = (dp2[i + 1][k + a] + dp2[i][k]) % mod

        ans = 0
        for i in range(N):
            ok = 1
            for k in range(K + 1):
                if dp[i][k] * dp2[N - i - 1][K - k] != 0:
                    ok = 0
                    break
            ans += ok

        print(ans)


if __name__ == '__main__':
    main()