#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <bitset>
#include <climits>
#include <cmath>
#include <bitset>
#include <complex>
#include <functional>
#include <cassert>
#include <stack>
#include <numeric>

typedef int64_t ll;
typedef std::pair<int, int> Pii;
typedef std::pair<ll, ll> Pll;
typedef std::pair<double, double> Pdd;

#define rip(i, n, _s) for (int i = (_s);i < (int)( n ); i++)
#define all(_l) _l.begin(), _l.end()
#define rall(_l) _l.rbegin(), _l.rend()
#define MM << " " <<

template<typename T>
using MaxHeap = std::priority_queue<T>;
template<typename T>
using MinHeap = std::priority_queue<T, std::vector<T>, std::greater<T>>;

template<typename T>
inline bool chmax(T &_l, const T b) {
    if (_l < b) {
        _l = b;
        return true;
    }
    return false;
}
template<typename T>
inline bool chmin(T &_l, const T b) {
    if (_l > b) {
        _l = b;
        return true;
    }
    return false;
}

# ifdef LOCAL_DEBUG
template<typename T>
void vdeb(const std::vector<T> &bb) {
    for (unsigned int i = 0;i < bb.size();i++) {
        if (i == bb.size() - 1) std::cout << bb[i];
        else std::cout << bb[i] << ' ';
    }
    std::cout << '\n';
}
template<typename T>
void vdeb(const std::vector<std::vector<T>> &bb) {
    for (unsigned int i = 0;i < bb.size();i++) {
        std::cout << i << ' ';
        vdeb(bb[i]);
    }
    std::cout << '\n';
}
# endif

using namespace std;

vector<vector<bool>> product(const vector<vector<bool>> &a, const vector<vector<bool>> &b) {
    int n = a.size();
    vector<vector<bool>> ret(n, vector<bool>(n));
    rip(i,n,0) rip(j,n,0) {
        rip(k,n,0) ret[i][j] = ret[i][j] | (a[i][k]&b[k][j]);
    }
    return ret;
}

int main() {
    int n, m; cin >> n >> m;
    ll t; cin >> t;
    vector<vector<bool>> da(n, vector<bool>(n));
    rip(i,m,0) {
        int a, b; cin >> a >> b;
        da[a][b] = true;
    }
    vector<vector<bool>> aft(n, vector<bool>(n));
    rip(i,n,0) aft[i][i] = true;
    while(t) {
        if(t&1) aft = product(aft, da);
        da = product(da, da);
        t >>= 1;
    }
    int ans = 0;
    rip(i,n,0) ans += aft[0][i];
    cout << ans << endl;
}