n, k = map(int, input().split())
A = list(map(int, input().split()))

dpl = [[False]*(k+1) for i in range(n+1)]
dpr = [[False]*(k+1) for i in range(n+1)]
dpl[0][0] = True
dpr[n][0] = True

for i, a in enumerate(A):
    for j in range(k+1):
        dpl[i+1][j] = dpl[i][j]
    for j in range(k+1):
        if dpl[i][j] and j+a <= k:
            dpl[i+1][j+a] = True

for i in range(n-1, -1, -1):
    a = A[i]
    for j in range(k+1):
        dpr[i][j] = dpr[i+1][j]
    for j in range(k+1):
        if dpr[i+1][j] and j+a <= k:
            dpr[i][j+a] = True

if not dpl[n][k]:
    print(-1)
    exit()

ans = 0
for i in range(n):
    flag = True
    for j in range(k+1):
        if dpl[i][j] and dpr[i+1][k-j]:
            flag = False
            break
    if flag:
        ans += 1
print(ans)