// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
#else
#define debug(x...)
#define Debug(x...)
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x), __VA_ARGS__})
#define cmax(x,...) x=max({(x), __VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define double long double
#define int long long
#define MAXN 200010
#define P 1000000007
struct graph {
struct node {
int v, w;
bool operator<(const node &other) const {
return w < other.w;
}
bool operator==(const node &other) const {
return v == other.v && w == other.w;
}
};
vector<vector<node>> e;
int n;
bool directed;
graph(int V, bool D = 0) {
n = V;
e.resize(n);
directed = D;
}
void add_edge(int u, int v, int w = 1) {
e[u].push_back(node{v, w});
}
int topo(vector<int> &vs) {
vector<int> din(n, 0);
for (auto es: e) for (auto edge: es) ++din[edge.v];
queue<int> q;
rep(i, 0, n) if (!din[i]) q.push(i);
vs.clear();
while (!q.empty()) {
int u = q.front(); q.pop();
vs.push_back(u);
for (auto [v, _]: e[u]) {
if (!--din[v]) q.push(v);
}
}
return sz(vs) == n;
}
void graphviz_dump(string filename = "graph.dot") {
ofstream gf; gf.open(filename);
gf << (directed ? "digraph" : "graph") << " {\n";
gf << " "; rep(i, 0, n) gf << i << " ;"[i==n-1]; gf << endl;
string notation = directed ? " -> " : " -- ";
bool weighted = 0;
for (auto es: e) for (auto edge: es) if (edge.w != 1) weighted = 1;
rep(u, 0, n) {
for (auto [v, w]: e[u]) {
if (!directed && u > v) continue;
gf << " " << u << notation << v << (weighted ? " ;\n" : ";\n");
}
}
gf << "}\n";
}
};
int32_t main() {
ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
int n, m; cin >> n >> m;
graph g(n, 1);
rep(i, 0, m) {
int u, v; cin >> u >> v;
g.add_edge(u-1, v-1);
}
g.graphviz_dump();
vector<int> vs; g.topo(vs);
vector<int> cnt(n, 0); cnt[0] = 1;
int st = 0; for (; vs[st] != 0; ++st);
rep(i, st, n) {
int u = vs[i];
for (auto [v, _]: g.e[u]) {
cnt[v] = (cnt[v] + cnt[u]) % P;
}
}
cout << cnt[n-1] << endl;
return 0;
}
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