n,m,l,r=map(int,input().split())
M=10**9+7
L=10**6
fa=[1,1]
fb=[1,1]
for i in range(2,L+1):
  fa+=[fa[-1]*i%M]
  fb+=[fb[-1]*(M//i)*fb[M%i]*fa[M%i-1]*(-1)%M]
c=lambda n,k:fa[n]*fb[k]*fb[n-k]%M if n>=k else 0
a=0
for i in range(m-(1+l*(n-1))+1):
  if (m-(1+l*(n-1))-i)%(r-l+1)==0 and (m-(1+l*(n-1))-i)//(r-l+1)<=n-1:
    a+=((-1)**(i%2))*c(n+1-1+i,i)*((-1)**(((m-(1+l*(n-1))-i)//(r-l+1))%2))*c(n-1,(m-(1+l*(n-1))-i)//(r-l+1))
    a%=M
print(a)