#include <bits/stdc++.h>
using namespace std;

constexpr int mod = 998244353;

long long modpow(long long a,long long b) {
    long long ans = 1;
    while(b) {
        if(b & 1) {
            (ans *= a) %= mod;
        }
        (a *= a) %= mod;
        b /= 2;
    }
    return ans;
}

int main() {
    int N,M;
    cin >> N >> M;
    int ans = 0,tmp = 1;
    for(int i = 29; i >= 0; i--) {
        if((1 << i) <= M) {
            ans += modpow(N+1,i)*tmp%mod;
            if(ans >= mod) ans -= mod;
            tmp = 1ll*N*tmp%mod;
            M -= (1 << i);
        }
    }
    ans += tmp;
    if(ans >= mod) ans -= mod;
    cout << ans << endl;
}