from sys import exit
n, k = map(int,input().split())
A = list(map(int,input().split()))

lDP=[[False for _ in range(k+1)] for _ in range(n+1)]
rDP=[[False for _ in range(k+1)] for _ in range(n+1)]

lDP[0][0]=True
for i in range(n):
    for j in range(k+1):
        lDP[i+1][j]=lDP[i][j]
    x=A[i]
    for j in range(k+1):
        if x+j>k:
            break
        if lDP[i][j]:
            lDP[i+1][j+x]=True

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

rDP[n][0]=True
for i in range(n,0,-1):
    for j in range(k+1):
        rDP[i-1][j]=rDP[i][j]
    x=A[i-1]
    for j in range(k+1):
        if x+j>k:
            break
        if rDP[i][j]:
            rDP[i-1][j+x]=True
ans=0

for i in range(n):
    use_flag = True
    for j in range(k+1):
        if lDP[i][j] and rDP[i+1][k-j]:
            use_flag = False
            break
    if use_flag:
        ans+=1

print(ans)