N,M=map(int,input().split())
mod=998244353
dp=[0]*(M+1)
dp[0]=1
for m in range(1,M+1):
    dp[m]+=dp[m-1]
    if 1<N and N<=m:
        dp[m]+=dp[m-N]
    dp[m]%=mod
ans=dp[M]
print(ans)