n,m=map(int,input().split())
mod=998244353

memo=dict()
def dp(m):
    if m==0:return 1
    if m in memo:return memo[m]
    res=0
    for b in range(2):
        res+=dp((m-b)//2)*pow(n,b,mod)
        res%=mod
    memo[m]=res
    return res
print(dp(m))