#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
const long long INF = 1e18;
const long long MAX = 100001;
struct mi {
  long long v;
  explicit operator long long() const { return v; }
  mi() { v = 0; }
  mi(long long _v) {
    v = (-MOD < _v && _v < MOD) ? _v : _v % MOD;
    if (v < 0) v += MOD;
  }
  friend bool operator==(const mi& a, const mi& b) { return a.v == b.v; }
  friend bool operator!=(const mi& a, const mi& b) { return !(a == b); }
  friend bool operator<(const mi& a, const mi& b) { return a.v < b.v; }
  mi& operator+=(const mi& m) {
    if ((v += m.v) >= MOD) v -= MOD;
    return *this;
  }
  mi& operator-=(const mi& m) {
    if ((v -= m.v) < 0) v += MOD;
    return *this;
  }
  mi& operator*=(const mi& m) {
    v = v * m.v % MOD;
    return *this;
  }
  mi& operator/=(const mi& m) { return (*this) *= inv(m); }
  friend mi pow(mi a, long long p) {
    mi ans = 1;
    assert(p >= 0);
    for (; p; p /= 2, a *= a)
      if (p & 1) ans *= a;
    return ans;
  }
  friend mi inv(const mi& a) {
    assert(a.v != 0);
    return pow(a, MOD - 2);
  }
  mi operator-() const { return mi(-v); }
  mi& operator++() { return *this += 1; }
  mi& operator--() { return *this -= 1; }
  mi operator++(int) {
    mi temp;
    temp.v = v++;
    return temp;
  }
  mi operator--(int) {
    mi temp;
    temp.v = v--;
    return temp;
  }
  friend mi operator+(mi a, const mi& b) { return a += b; }
  friend mi operator-(mi a, const mi& b) { return a -= b; }
  friend mi operator*(mi a, const mi& b) { return a *= b; }
  friend mi operator/(mi a, const mi& b) { return a /= b; }
  friend ostream& operator<<(ostream& os, const mi& m) {
    os << m.v;
    return os;
  }
  friend istream& operator>>(istream& is, mi& m) {
    long long x;
    is >> x;
    m.v = x;
    return is;
  }
};
void solve() {
  long long n, k;
  cin >> n >> k;
  set<int> s;
  mi ans = 0;
  mi dp[n + 1];
  dp[1] = 1;
  dp[0] = 0;
  for (int i = 0; i < k; i++) {
    int fst, snd;
    cin >> fst >> snd;
    s.insert(fst);
    s.insert(snd);
  }
  for (int i = 2; i <= n; i++) {
    dp[i] = 0;
    for (int num : s)
      if (i - num > 0) dp[i] += dp[i - num];
  }
  cout << dp[n];
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  long long t;
  t = 1;
  for (int i = 1; i <= t; i++) {
    solve();
  }
  return 0;
}
