n,m=map(int,input().split())
if n==1:
  exit(print(1))
ans=0
mod=998244353
f = [1]
for i in range(m*2):
  f += [f[-1]*(i+1) % mod]
def comb(a, b):
  return f[a]*pow(f[b], mod-2, mod)*pow(f[a-b], mod-2, mod) % mod
for i in range(m+1):
  if (m-i)%n:continue
  ans+=comb((m-i)//n+i,i)
  ans%=mod
print(ans)