import collections,sys,math,functools,operator,itertools,bisect,heapq,decimal,string,time,random
input = sys.stdin.readline
sys.set_int_max_str_digits(0)
class comb():
    def __init__(self,n,mod):
        self.fact = [0] * (n+1)
        self.fact_inv = [0] * (n+1)
        self.mod = mod

        self.fact[1] = 1
        self.fact_inv[1] = pow(1,mod-2,mod)
        self.fact[0] = 1
        self.fact_inv[0] = 1

        for i in range(2,n+1):
            self.fact[i] = (self.fact[i-1] * i) % mod
            self.fact_inv[i] = (self.fact_inv[i-1] * pow(i,mod-2,mod)) % mod
    def ncr(self,n,r):
        if n-r < 0:
            return 0
        return (self.fact[n] * self.fact_inv[r] * self.fact_inv[n-r]) % self.mod
    def nhr(self,n,r):
        return self.ncr(n+r-1,r)
mod = 998244353
c = comb(2000000,mod)
n,m = map(int,input().split())
if n == 1:
    ans = 0
    minv = pow(m,mod-2,mod)
    for i in range(m):
        ans += i * minv
        ans %= mod
    print(ans)
    exit()
ans = 0
p = 0
for i in range(m):
    x = m - i * n
    if x < 0:continue
    y = c.nhr(n+1,x)
    if i == 0:
        y -= n
        p = pow(y,mod-2,mod)
        continue
    #print(i,y,pow(p,mod-2,mod))
    ans += p * y
    ans %= mod
print(ans)