#include <iostream>
#include <vector>
using namespace std;
typedef long long ll;
ll INF = 1000000000000000;
struct segment_tree{
    int n; vector<ll> seg;
    ll e(){return 0;}
    ll op(ll a,ll b){return (a + b);}
    segment_tree(){}
    segment_tree(int sz){n = sz; seg.resize(2*n);}
    segment_tree(vector<ll> v){
        n = v.size(); seg.resize(2*n);
        for(int i=0;i<n;i++) seg[i + n] = v[i];
        for(int i=n - 1;i>0;i--) seg[i] = op(seg[i<<1],seg[i<<1|1]);
    }
    void init(int sz){n = sz; seg.resize(2*n);}
    void update(int p,ll val){
        for(seg[p += n] = val;p>1;p>>=1) seg[p>>1] = op(seg[p],seg[p^1]);
    }
    ll get(int p){return seg[p + n];}
    ll query(int l,int r){
        ll res = e();
        for(l += n,r += n; l<r;l>>=1,r>>=1){
            if(l&1) res = op(res,seg[l++]);
            if(r&1) res = op(res,seg[--r]);
        }
        return res;
    }
    void clear(){for(int i=0;i<2*n;i++) seg[i] = 0;}
};

ll mod = 998244353;
ll pw(ll a,ll x){
    ll ret = 1;
    while(x){
        if(x&1) (ret *= a) %= mod;
        (a *= a) %= mod; x /= 2;
    }
    return ret;
}
int p[200010];
int main(){
    int i,n,m; cin >> n >> m;
    for(i=0;i<n;i++) p[i] = -1;
    for(i=0;i<m;i++){
        int a,b; cin >> a >> b; a--; b--;
        p[b] = a;
    }
    ll c = 0,ans = 0;
    segment_tree seg(n),seg_clear(n);
    for(i=0;i<n;i++) seg_clear.update(i,1);
    for(i=0;i<n;i++){
        if(p[i]!=-1) seg_clear.update(p[i],0);
    }
    segment_tree seg2(n);
    for(i=0;i<n;i++){
        if(p[i]!=-1){
            seg.update(p[i],1);
            (ans += seg.query(p[i] + 1,n)) %= mod; 
            ll num = seg_clear.query(0,n);
            (ans += seg_clear.query(p[i],n)*c%mod*pw(num,mod - 2)%mod) %= mod;
            seg2.update(p[i],num - c);
        }else{
            c++;
        }
    }
    ll num = seg_clear.query(0,n);
    (ans += (num*(num - 1)/2)%mod*(mod + 1)/2%mod) %= mod;
    for(i=0;i<n;i++){
        if(seg_clear.get(i)){
            (ans += seg2.query(i,n)*pw(num,mod - 2)) %= mod;
        }
    }
    for(i=1;i<=num;i++) (ans *= i) %= mod;
    cout << ans << "\n";
}