#include <iostream>
#include <vector>
using namespace std;
using ll = long long int;
using Matrix = vector<vector<int>>;

Matrix matpow(Matrix mat, ll t){
    const int n = mat.size();
    Matrix ans = Matrix(n, vector<int>(n, 0));
    for(int i = 0; i < n; i++) ans[i][i] = 1;
    while(t > 0){
        if(t & 1){
            Matrix newans = Matrix(n, vector<int>(n, 0));
            for(int i = 0; i < n; i++){
                for(int j = 0; j < n; j++){
                    for(int k = 0; k < n; k++) newans[i][j] |= ans[i][k] * mat[k][j];
                }
            }
            ans = newans;
        }
        Matrix newmat = Matrix(n, vector<int>(n, 0));
        for(int i = 0; i < n; i++){
            for(int j = 0; j < n; j++){
                for(int k = 0; k < n; k++) newmat[i][j] |= mat[i][k] * mat[k][j];
            }
        }
        mat = newmat;
        t >>= 1;
    }
    return ans;
}

int main(){
    ll n, m, t;
    cin >> n >> m >> t;
    Matrix mat = Matrix(n, vector<int>(n, 0));
    for(int i = 0; i < m; i++){
        int a, b;
        cin >> a >> b;
        mat[b][a] = 1;
    }
    mat = matpow(mat, t);
    int ans = 0;
    for(int i = 0; i < n; i++) ans += mat[i][0];
    cout << ans << endl;
    return 0;
}