#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstring>
#include <cstdlib>
#include <cmath>
using namespace std;
using ll = long long;

template <class T, int N>
struct ColumnVector {
    struct SquareMatrix {
        static SquareMatrix E() {
            SquareMatrix r;
            for (int i = 0; i < N; i++) {
                for (int j = 0; j < N; j++) {
                    r.a[i][j] = i == j;
                }
            }
            return r;
        }
        ColumnVector operator*(const ColumnVector &v) const {
            ColumnVector r;
            for (int i = 0; i < N; i++) {
                T t = 0;
                for (int k = 0; k < N; k++) {
                    t += a[i][k] * v.a[k];
                }
                r.a[i] = t != 0;
            }
            return r;
        }
        SquareMatrix operator*(const SquareMatrix &x) const {
            SquareMatrix r;
            for (int i = 0; i < N; i++) {
                for (int j = 0; j < N; j++) {
                    T t = 0;
                    for (int k = 0; k < N; k++) {
                        t += a[i][k] * x.a[k][j];
                    }
                    r.a[i][j] = t != 0;
                }
            }
            return r;
        }
        SquareMatrix pow(ll k) const {
            SquareMatrix r = E(), t = *this;
            for (; k != 0; k /= 2) {
                if (k & 1) r = r * t;
                t = t * t;
            }
            return r;
        }
        void print() const {
            for (int i = 0; i < N; i++) {
                for (int j = 0; j < N; j++) {
                    cout << a[i][j].i << " \n"[j == N - 1];
                }
            }
        }
        T a[N][N];
    };
    void print() const {
        for (int i = 0; i < N; i++) {
            cout << a[i].i << " \n"[i == N - 1];
        }
    }
    T a[N];
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, m;
    cin >> n >> m;

    ll t;
    cin >> t;

    ColumnVector<int, 100> v;
    for (int i = 0; i < n; i++) {
        v.a[i] = i == 0;
    }

    ColumnVector<int, 100>::SquareMatrix x;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            x.a[i][j] = 0;
        }
    }
    for (int i = 0; i < m; i++) {
        int a, b;
        cin >> a >> b;

        x.a[b][a] = 1;
    }

    v = x.pow(t) * v;

    int r = 0;
    for (int i = 0; i < n; i++) {
        r += v.a[i];
    }

    cout << r << endl;

    return 0;
}