N,K=map(int,input().split())
A=list(map(int,input().split()))
from bisect import bisect_right as br

A.sort()

rem=[0]*(N+1)
for i in range(N-1,-1,-1 ):
    r=K-A[i]
    idx=min(br(A,r),i)
    rem[i]=idx
ans=1
mod=10**9+7
n=0
for i in range(N-1,-1,-1):
    ans=ans*(rem[i]-n)%mod
    n+=1
    
print(ans%mod)