#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const ll ILL=2167167167167167167;
const int INF=2100000000;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define all(p) p.begin(),p.end()
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> int UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,T b){if(b<a){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,T b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
bool yneos(bool a,bool upp=false){if(a){cout<<(upp?"YES\n":"Yes\n");}else{cout<<(upp?"NO\n":"No\n");}return a;}
template<class T> void vec_out(vector<T> &p,int ty=0){
    if(ty==2){cout<<'{';for(int i=0;i<(int)p.size();i++){if(i){cout<<",";}cout<<'"'<<p[i]<<'"';}cout<<"}\n";}
    else{if(ty==1){cout<<p.size()<<"\n";}for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout<<p[i];}cout<<"\n";}}
template<class T> T vec_min(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;}
template<class T> T vec_max(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;}
template<class T> T vec_sum(vector<T> &a){T ans=T(0);for(auto &x:a) ans+=x;return ans;}
int pop_count(long long a){int res=0;while(a){res+=(a&1),a>>=1;}return res;}
template<class T> T square(T a){return a * a;}

random_device seed_gen;
mt19937 rng(seed_gen());
// return [l, r)
long long rand_long(long long l,long long r){
    return uniform_int_distribution<long long>(l,r-1)(rng);
}

#include <atcoder/modint>
using mint = atcoder::modint998244353;

void solve();
// POP'N ROLL MUSIC / TOMOO
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    // cin >> t;
    rep(i, 0, t) solve();
}

void solve(){
    ll N, M;
    cin >> N >> M;
    vector<pair<ll, ll>> p;
    rep(i, 0, M){
        ll l, r;
        cin >> l >> r;
        ll h = rand_long(0, 1ll << 60);
        p.push_back({l - 1, h});
        p.push_back({r, h});
    }
    So(p);
    ll X = 0;
    vector<mint> A;
    vector<pair<ll, mint>> q;
    mint OK = 0;
    ll tmp = 0;
    for (auto [a, del] : p){
        if (tmp){
            q.push_back({tmp, a - X});
        }
        else{
            OK += a - X;
        }
        X = a;
        tmp ^= del;
    }
    OK += N - X;
    {
        sort(all(q), [&](auto l, auto r){
            return l.first < r.first;
        });
        for (int l = 0, r = 0; l < (int)q.size(); l = r){
            mint s = 0;
            while (r != (int)q.size() && q[l].first == q[r].first){
                s += q[r].second;
                r++;
            }
            A.push_back(s);
        }
    }
    mint ans = 0;
    ans += (mint(N)) * (mint(N - 1));
    ans += OK * 4;
    for (auto a : A){
        ans += a * OK * 2;
        ans += a * (a - 1);
        ans += a * 2;
    }
    ans += OK * (OK - 1) * 3;
    ans *= (mint(2)).pow(M);
    ans /= 4;
    cout << ans.val() << "\n";
}