#include <string.h>
#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <ctime>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <memory>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#include <atcoder/all>
using namespace std;
using namespace atcoder;

constexpr int mod = 998244353;

long long fac[200005], finv[200005], inv[200005];

void COMinit() {
    fac[0] = fac[1] = finv[0] = finv[1] = inv[1] = 1;
    for (int i = 2; i < 200005; i++) {
        fac[i] = fac[i - 1] * i % mod;
        inv[i] = mod - inv[mod % i] * (mod / i) % mod;
        finv[i] = finv[i - 1] * inv[i] % mod;
    }
}

long long COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % mod) % mod;
}

long long choose(int n,int k) {
    if(n < 0 || k < 0) return 0;
    if(n == 0) return 1;
    return COM(n+k-1,k-1);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N,M;
    cin >> N >> M;
    if(N%2) {
        cout << 0 << "\n";
        return 0;
    }
    COMinit();
    vector<pair<vector<int>,vector<int>>>tmp;
    for(int i = 0; i < M; i++) {
        int L,R;
        cin >> L >> R;
        L--;
        if((R-L)%2) continue;
        vector<int>a(R-L+1),b(R-L+1);
        a[0] = 1;
        b[R-L] = (COM(R-L,(R-L)/2)+mod-COM(R-L,(R-L)/2+1))%mod;
        tmp.push_back({a,b});
    }
    while(tmp.size() > 1) {
        vector<pair<vector<int>,vector<int>>>nxt;
        for(int i = 0; i < tmp.size(); i += 2) {
            if(i+1 == tmp.size()) {
                nxt.push_back(tmp[i]);
            }
            else {
                auto a1 = convolution(tmp[i].first,tmp[i+1].first);
                auto a2 = convolution(tmp[i].second,tmp[i+1].second);
                auto b1 = convolution(tmp[i].first,tmp[i+1].second);
                auto b2 = convolution(tmp[i].second,tmp[i+1].first);
                for(int i = 0; i < a1.size(); i++) {
                    a1[i] += a2[i];
                    if(a1[i] >= mod) a1[i] -= mod;
                    b1[i] += b2[i];
                    if(b1[i] >= mod) b1[i] -= mod;
                }
                nxt.push_back({a1,b1});
            }
        }
        tmp = nxt;
    }
    if(tmp.empty()) {
        cout << (COM(N,N/2)+mod-COM(N,N/2+1))%mod << "\n";
        return 0;
    }
    int ans = 0;
    for(int i = 0; i < tmp[0].first.size(); i += 2) {
        ans += (COM(N-i,(N-i)/2)+mod-COM(N-i,(N-i)/2+1))%mod*tmp[0].first[i]%mod;
        if(ans >= mod) ans -= mod;
        ans += mod-(COM(N-i,(N-i)/2)+mod-COM(N-i,(N-i)/2+1))%mod*tmp[0].second[i]%mod;
        if(ans >= mod) ans -= mod;
    }
    cout << ans << "\n";
}