import sys
from itertools import permutations
from heapq import heappop,heappush
from collections import deque
import random
import bisect

input = lambda :sys.stdin.readline().rstrip()
mi = lambda :map(int,input().split())
li = lambda :list(mi())

"""
E[prod x_i^a_i] = prod 1/(ai+1)

sum a_i = K を満たすすべての a に対する
K! * prod 1/(ai+1)! の総和

1/1!+x/2!+x^2/3!+... = (e^x-1)/x

K! [x^K] (e^x-1)^N/x^N
= K! [x^(N+K)] (e^x-1)^N
"""

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    return (g1[n] * g2[r] % mod) * g2[n-r] % mod


mod = 998244353
N = 10**6 + 100 + 10**7
g1 = [1]*(N+1)
g2 = [1]*(N+1)
inverse = [1]*(N+1)

for i in range( 2, N + 1 ):
    g1[i]=( ( g1[i-1] * i ) % mod )
    inverse[i]=( ( -inverse[mod % i] * (mod//i) ) % mod )
    g2[i]=( (g2[i-1] * inverse[i]) % mod )
inverse[0]=0

N,K = mi()
res = 0
for i in range(N+1):
    if (N-i) & 1:
        res -= cmb(N,i,mod) * pow(i,N+K,mod) % mod
    else:
        res += cmb(N,i,mod) * pow(i,N+K,mod) % mod
    res %= mod

res *= g1[K] * g2[N+K] % mod
res %= mod

res *= pow(inverse[N],K,mod)
res %= mod

print(res % mod)