import sys
input = sys.stdin.readline

mod=998244353

FACT=[1]
for i in range(1,5*10**6+1):
    FACT.append(FACT[-1]*i%mod)

FACT_INV=[pow(FACT[-1],mod-2,mod)]
for i in range(5*10**6,0,-1):
    FACT_INV.append(FACT_INV[-1]*i%mod)

FACT_INV.reverse()

def Combi(a,b):
    if 0<=b<=a:
        return FACT[a]*FACT_INV[b]%mod*FACT_INV[a-b]%mod
    else:
        return 0

N,M=map(int,input().split())

ANS=0

ALL=Combi(N+M,N)-N

y=M
k=0
while True:
    y-=N
    k+=1

    if y<0:
        break
    
    ANS+=Combi(N+y,y)

if N==1:
    ANS-=M

print(ANS*pow(ALL,mod-2,mod)%mod)