#include <bits/stdc++.h>
#include <atcoder/modint>
using namespace std;
using ll = long long;
using mint = atcoder::modint998244353;
const ll INF = LLONG_MAX / 4;
#define rep(i,a,b) for(ll i = a; i < b; i++)
template<class T, class U> bool chmax(T& a, U b){ if(a >= b) return 0; a = b; return 1; }


int main(){
    ll N, M;
    cin >> N >> M;
    cout << mint{max(0LL, N - M + 1)}.val() << endl;
}