#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001


int main(){
	
	int N,M;
	cin>>N>>M;
	
	vector<pair<int,int>> t(M);
	rep(i,M){
		cin>>t[i].second>>t[i].first;

	}
	sort(t.begin(),t.end());
	fenwick_tree<mint> F(N+1);
	mint ans = 0;
	rep(i,M){
		ans += F.sum(t[i].second,N+1);
		F.add(t[i].second,1);
	}
	
	if(N!=M){
		vector<int> vs;
		rep(i,M)vs.push_back(t[i].second);
		sort(vs.begin(),vs.end());
		rep(i,M){
			mint tt = distance(upper_bound(vs.begin(),vs.end(),t[i].second),vs.end());
			tt = (N-t[i].second) - tt;
			tt /= N-M;
			tt *= t[i].first-1-i;
			ans += tt;
		}
		
		reverse(t.begin(),t.end());
		rep(i,t.size()){
			t[i].first = N+1-t[i].first;
			t[i].second = N+1-t[i].second;
		}
		rep(i,vs.size()){
			vs[i] = N+1-vs[i];
		}
		sort(vs.begin(),vs.end());
		rep(i,M){
			mint tt = distance(upper_bound(vs.begin(),vs.end(),t[i].second),vs.end());
			tt = (N-t[i].second) - tt;
			tt /= N-M;
			tt *= t[i].first-1-i;
			ans += tt;
		}
		
		{
			mint cur = N-M;
			cur *= N-M-1;
			cur /= 2;
			cur /= 2;
			ans += cur;
		}
	}
	rep(i,N-M){
		ans *= i+1;
	}
	
	cout<<ans.val()<<endl;
	
	return 0;
}