#include <iostream>
#include <vector>
#include <set>
#include <numeric>
#include <algorithm>

using namespace std;

using vi = vector<int>;
using v2i = vector<vi>;
using si = set<int>;

constexpr int Z = 998244353;

int fi(int f[], int u) {
    return f[u] == u ? u : f[u] = fi(f, f[u]);
}

int main() {
    int n, m;
    cin >> n >> m;
    si to[n];
    vi e[n];
    for (int i = 0; i < m; i++) {
        int u, v;
        cin >> u >> v;
        u--; v--;
        e[v].push_back(u);
        to[u].insert(v);
    }

    int f[n], add[n];
    iota(f, f + n, 0);
    fill(add, add + n, 0);

    int dp[n];
    fill(dp, dp + n, 1);
    int ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j : e[i]) {
            int u = fi(f, i), v = fi(f, j);
            if (u != v) {
                dp[i] = (dp[i] + add[v]) % Z;
                to[v].erase(i);

                if (to[u].size() < to[v].size()) {
                    swap(u, v);
                }

                for (int w : to[v]) {
                    dp[w] = (dp[w] + add[v]) % Z;
                    if (!to[u].count(w)) {
                        dp[w] = (dp[w] - add[u] + Z) % Z;
                        to[u].insert(w);
                    }
                }

                f[v] = u;
                to[v].clear();
            }
        }

        int u = fi(f, i);
        add[u] = (add[u] + dp[i]) % Z;
        ans = (ans + dp[i]) % Z;
    }

    cout << ans << endl;

    return 0;
}