#include <bits/stdc++.h>
#include <random>
using namespace std; typedef unsigned long long _ulong; typedef long long int lint; typedef pair<lint, lint> plint; typedef pair<double long, double long> pld;
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((lint)(x).size())
#define FOR(i, begin, end) for(lint i=(begin),i##_end_=(end);i<i##_end_;++i)
#define IFOR(i, begin, end) for(lint i=(end)-1,i##_begin_=(begin);i>=i##_begin_;--i)
#define REP(i, n) FOR(i,0,n)
#define IREP(i, n) IFOR(i,0,n)
#define endk '\n'
#define fi first
#define se second
struct fast_ios { fast_ios() { cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); }; } fast_ios_;
template<class T> auto add = [](T a, T b) -> T { return a + b; };
template<class T> auto f_max = [](T a, T b) -> T { return max(a, b); };
template<class T> auto f_min = [](T a, T b) -> T { return min(a, b); };
template<class T> using V = vector<T>;
using Vl = V<lint>; using VVl = V<Vl>;
template< typename T > ostream& operator<<(ostream& os, const vector< T >& v) {
	for (int i = 0; i < (int)v.size(); i++) os << v[i] << (i + 1 != v.size() ? " " : "");
	return os;
}
template< typename T >istream& operator>>(istream& is, vector< T >& v) {
	for (T& in : v) is >> in;
	return is;
}
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return 1; } return 0; }
lint gcd(lint a, lint b) { if (b == 0) return a; else return gcd(b, a % b); }
lint ceil(lint a, lint b) { return (a + b - 1) / b; }
lint digit(lint a) { return (lint)log10(a); }
lint e_dist(plint a, plint b) { return abs(a.fi - b.fi) * abs(a.fi - b.fi) + abs(a.se - b.se) * abs(a.se - b.se); }
lint m_dist(plint a, plint b) { return abs(a.fi - b.fi) + abs(a.se - b.se); }
void Worshall_Floyd(VVl& g) { REP(k, SZ(g)) REP(i, SZ(g)) REP(j, SZ(g)) chmin(g[i][j], g[i][k] + g[k][j]); }
const lint MOD = 1e9 + 7, INF = 1e18;
lint dx[8] = { 1, 0, -1, 0, 1, -1, 1, -1 }, dy[8] = { 0, 1, 0, -1, -1, -1, 1, 1 };
bool YN(bool flag) { cout << (flag ? "YES" : "NO") << endk; return flag; } bool yn(bool flag) { cout << (flag ? "Yes" : "No") << endk; return flag; }
struct Edge {
	lint from, to;
	lint cost;
	Edge(lint u, lint v, lint c) {
		cost = c;
		from = u;
		to = v;
	}
	bool operator<(const Edge& e) const {
		return cost < e.cost;
	}
};
struct WeightedEdge {
	lint to;
	lint cost;
	WeightedEdge(lint v, lint c = 1) {
		to = v;
		cost = c;
	}
	bool operator<(const WeightedEdge& e) const {
		return cost < e.cost;
	}
};
using WeightedGraph = V<V<WeightedEdge>>;
typedef pair<lint, plint> tlint;
typedef pair<plint, plint> qlint;
typedef pair<string, lint> valstring;

template <std::int_fast64_t Modulus>
class modint
{
	using u64 = std::int_fast64_t;

public:
	u64 a;
	constexpr modint(const u64 x = 0) noexcept : a(x% Modulus) {}
	constexpr u64& value() noexcept { return a; }
	constexpr const u64& value() const noexcept { return a; }
	constexpr modint operator+(const modint rhs) const noexcept
	{
		return modint(*this) += rhs;
	}
	constexpr modint operator-(const modint rhs) const noexcept
	{
		return modint(*this) -= rhs;
	}
	constexpr modint operator*(const modint rhs) const noexcept
	{
		return modint(*this) *= rhs;
	}
	constexpr modint operator/(const modint rhs) const noexcept
	{
		return modint(*this) /= rhs;
	}
	constexpr modint& operator+=(const modint rhs) noexcept
	{
		a += rhs.a;
		if (a >= Modulus)
		{
			a -= Modulus;
		}
		return *this;
	}
	constexpr modint& operator-=(const modint rhs) noexcept
	{
		if (a < rhs.a)
		{
			a += Modulus;
		}
		a -= rhs.a;
		return *this;
	}
	constexpr modint& operator*=(const modint rhs) noexcept
	{
		a = a * rhs.a % Modulus;
		return *this;
	}
	constexpr modint& operator/=(modint rhs) noexcept
	{
		u64 exp = Modulus - 2;
		while (exp)
		{
			if (exp % 2)
			{
				*this *= rhs;
			}
			rhs *= rhs;
			exp /= 2;
		}
		return *this;
	}
};
typedef modint<MOD> ModInt;

ModInt mod_pow(ModInt x, lint n) {
	ModInt ret = 1;
	while (n > 0) {
		if (n & 1) (ret *= x);
		(x *= x);
		n >>= 1;
	}
	return ret;
}


template<typename T>
struct Matrix_Powers {
public:
	V<V<T>> Matrix;
	V<T> dp;
	int sz;
	Matrix_Powers(int _sz) : Matrix(_sz, V<T>(_sz, 0)), dp(_sz, 0), sz(_sz) {
	};

	void Matrix_Pow(lint k) {
		while (k) {
			if (k & 1) Matrix_Mul();
			Update();
			k /= 2;
		}
	}

private:
	void Matrix_Mul() {
		V<T> res(sz);
		REP(i, sz) REP(j, sz) res[i] += Matrix[i][j] * dp[j];
		dp = res;
	}

	void Update() {
		V<V<T>> res(sz, V<T>(sz));
		REP(i, sz) {
			REP(j, sz) {
				REP(k, sz) {
					res[i][j] += Matrix[i][k] * Matrix[k][j];
				}
			}
		}
		Matrix = res;
	}
};

lint N, M, T, u, v;
int main() {
	cin >> N >> M >> T;
	VVl mat(N, Vl(N, 0));
	Matrix_Powers<ModInt> mat_pow(N);
	REP(i, M) {
		cin >> u >> v;
		mat_pow.Matrix[v][u] = 1;
	}
	mat_pow.dp[0] = 1;
	mat_pow.Matrix_Pow(T);
	lint ans = 0;
	REP(i, N) ans += mat_pow.dp[i].a != 0;
	cout << ans << endk;
}