#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m, p, k, rem;
    cin >> n >> m;
    vector<pair<int,int>> a(m);
    vector<int> s2(n + 1, 1);
    for(int i = 0; i < m; i++){
        cin >> p >> k;
        s2[k]--;
        a[i] = make_pair(--p, --k);
    }
    sort(a.begin(), a.end());
    for(int i = 0; i < n; i++) s2[i + 1] += s2[i];
    rem = n - m;
    mint ans, fr, ba, up, down, ten;
    fenwick_tree<int> fw(n);
    for(int i = 0; i < m; i++){
        tie(p, k) = a[i];
        fr = p - i, ba = n - p - (m - i);
        down = s2[k] - 1, up = s2[n] - s2[k];
        ans += fr * up + ba * down;
        ten += fw.sum(k, n);
        fw.add(k, 1);
    }
    if(rem) ans /= rem;
    ans += mint(rem) * (rem - 1) / 4 + ten;
    for(int i = 2; i <= rem; i++) ans *= i;
    cout << ans.val() << '\n';
}