#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")

////////////////////////////////////////////////////////////////////////////////
template <unsigned M_> struct ModInt {
  static constexpr unsigned M = M_;
  unsigned x;
  constexpr ModInt() : x(0U) {}
  constexpr ModInt(unsigned x_) : x(x_ % M) {}
  constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
  constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
  constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
  ModInt &operator+=(const ModInt &a) { x = ((x += a.x) >= M) ? (x - M) : x; return *this; }
  ModInt &operator-=(const ModInt &a) { x = ((x -= a.x) >= M) ? (x + M) : x; return *this; }
  ModInt &operator*=(const ModInt &a) { x = (static_cast<unsigned long long>(x) * a.x) % M; return *this; }
  ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
  ModInt pow(long long e) const {
    if (e < 0) return inv().pow(-e);
    ModInt a = *this, b = 1U; for (; e; e >>= 1) { if (e & 1) b *= a; a *= a; } return b;
  }
  ModInt inv() const {
    unsigned a = M, b = x; int y = 0, z = 1;
    for (; b; ) { const unsigned q = a / b; const unsigned c = a - q * b; a = b; b = c; const int w = y - static_cast<int>(q) * z; y = z; z = w; }
    assert(a == 1U); return ModInt(y);
  }
  ModInt operator+() const { return *this; }
  ModInt operator-() const { ModInt a; a.x = x ? (M - x) : 0U; return a; }
  ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
  ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
  ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
  ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
  template <class T> friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
  template <class T> friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
  template <class T> friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
  template <class T> friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
  explicit operator bool() const { return x; }
  bool operator==(const ModInt &a) const { return (x == a.x); }
  bool operator!=(const ModInt &a) const { return (x != a.x); }
  friend std::ostream &operator<<(std::ostream &os, const ModInt &a) { return os << a.x; }
};
////////////////////////////////////////////////////////////////////////////////

constexpr unsigned MO = 998244353;
using Mint = ModInt<MO>;


vector<int> uf;
int root(int u) {
  return (uf[u] < 0) ? u : (uf[u] = root(uf[u]));
}
bool connect(int u, int v) {
  u = root(u);
  v = root(v);
  if (u == v) return false;
  if (uf[u] > uf[v]) swap(u, v);
  uf[u] += uf[v];
  uf[v] = u;
  return true;
}


int N, M;
vector<int> A, B;

vector<vector<int>> graph, hparg;

int main() {
  for (; ~scanf("%d%d", &N, &M); ) {
    A.resize(M);
    B.resize(M);
    for (int i = 0; i < M; ++i) {
      scanf("%d%d", &A[i], &B[i]);
      --A[i];
      --B[i];
      if (A[i] > B[i]) {
        swap(A[i], B[i]);
      }
    }
    
    graph.assign(N, {});
    hparg.assign(N, {});
    for (int i = 0; i < M; ++i) {
      graph[A[i]].push_back(B[i]);
      hparg[B[i]].push_back(A[i]);
    }
    
    uf.assign(N, -1);
    vector<Mint> dp(N, 0);
    vector<Mint> lz(N, 0);
    vector<set<int>> neiss(N);
    for (int u = 0; u < N; ++u) {
// cerr<<COLOR("33")<<"u = "<<u<<COLOR()<<endl;
      vector<int> rvs;
      for (const int v : hparg[u]) {
        rvs.push_back(root(v));
      }
      sort(rvs.begin(), rvs.end());
      rvs.erase(unique(rvs.begin(), rvs.end()), rvs.end());
      int ru = root(u);
      for (const int rv : rvs) {
        assert(ru != rv);
        if (neiss[ru].size() < neiss[rv].size()) {
          swap(lz[ru], lz[rv]);
          swap(neiss[ru], neiss[rv]);
        }
        for (const int v : neiss[rv]) {
          dp[v] += lz[rv];
          if (neiss[ru].insert(v).second) {
            dp[v] -= lz[ru];
          }
        }
        lz[rv] = 0;
        neiss[rv].clear();
        connect(ru, rv);
        if (root(ru) == rv) {
          swap(lz[ru], lz[rv]);
          swap(neiss[ru], neiss[rv]);
        }
        ru = root(ru);
      }
      for (const int v : graph[u]) {
        if (neiss[ru].insert(v).second) {
          dp[v] -= lz[ru];
        }
      }
      {
        auto it = neiss[ru].find(u);
        if (it != neiss[ru].end()) {
          dp[u] += lz[ru];
          neiss[ru].erase(it);
        }
      }
      dp[u] += 1;
      lz[ru] += dp[u];
// cerr<<"  dp = "<<dp<<endl;
// cerr<<"  lz = "<<lz<<endl;
// for(int r=0;r<N;++r)if(uf[r]<0){cerr<<"  neiss["<<r<<"] = ";pv(neiss[r].begin(),neiss[r].end());}
    }
// cerr<<"dp = "<<dp<<endl;
    
    Mint ans = 0;
    for (int u = 0; u < N; ++u) {
      ans += dp[u];
    }
    printf("%u\n", ans.x);
  }
  return 0;
}