// g++ 1.cpp -std=c++17 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

#include <atcoder/all>
using namespace atcoder;

using ll = long long;
using ld = long double;
 
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;
using vst = vector<string>;
using vvst = vector<vst>;
 
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

using mint = modint998244353;

int op(int a,int b){
  return (int)a+b;
}

int e(){
  return 0;
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  ll n,k;cin>>n>>k;
  mint ans=0;
  ans=((n-k)*(n-k-1));
  ans/=4;

  vi v(n,-1),x(n,1);
  rep(i,0,k){
    int p,q;cin>>p>>q;
    p--;q--;
    v[q]=p;
    x[p]=0;
  }

  mint now=0;
  segtree<int,op,e> seg(n),seg2(x);
  per(i,n-1,0){
    if(v[i]==-1){
      ans+=now; // ? - fix
    }
    else{
      ans+=seg.prod(0,v[i]);
      seg.set(v[i],1);
      //now+=(mint)seg2.prod(v[i],n)/(n-k);
    }
  }

  now=0;
  rep(i,0,n){
    if(v[i]==-1){
      ans+=now; // fix - ?
    }
    else{
      //now+=(mint)seg2.prod(0,v[i])/(n-k); 
    }
  }

  rep(i,0,n-k){
    ans*=i+1;
  }

  cout<<ans.val()<<endl;
}