#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#define int long long
using namespace std;
const int N = 5e5 + 10, mod = 80112002;
int h[N], e[N], ne[N], idx;
int in[N], out[N];
int q[N];
int num[N];
int n, m, ans;
void add(int a, int b)
{
    e[idx] = b;
    ne[idx] = h[a];
    h[a] = idx++;
}
int topsort()
{
    int hh = 0, tt = -1;
    for (int i = 1; i <= n; i++)
        if(!in[i])
        {
            num[i] = 1;
            q[++tt] = i;
        }
            
    while(hh <= tt)
    {
        int t = q[hh++];
        for (int i = h[t]; i != -1; i = ne[i])
        {
            int j = e[i];
            --in[j];
            num[j] = (num[j] + num[t]) % mod;
            if(in[j] == 0)
                q[++tt] = j;
        }
    }
    for (int i = 1; i <= n; i++)
    {
        if(!out[i])
            ans = (ans + num[i]) % mod;
    }
    return ans;
}
signed main ()
{
    // ios::sync_with_stdio(false);
    // cin.tie(0);
    // cout.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int x, y;
        cin >> x >> y;
        add(x, y);
        in[y]++;
        out[x]++;
    }
    int res = topsort();
    cout << res << endl;
    return 0;
}

所有数据都TLE了，时间复杂度在哪块大了呢？