N,K=map(int,input().split())
P=998244353
def C(x,y):
	a=1
	for i in range(y):a=(a*(x-i)*pow(i+1,-1,P))%P
	return a
a=C(2*N+4,K)
b=[C(N+2,K//2),0][K%2]
c=max([C(N+2,K//2),[0,C(N+1,K//2)*2][N%2]][K%2],0)
d=b
print([(a+b+c+d)*pow(4,-1,P)%P,[1,1,3,3,3,1,1][K]][N<2])