mod=10**9+7
n,m=list(map(int,input().split()))
r=1
for i in range(m-n+1,m+2):
    r=(r*i)%mod

inv=[0,1]
for i in range(2,n+2):
    inv.append((mod-inv[mod%i]*(mod//i))%mod)
    r=(r*inv[-1])%mod

print(r)