#include<bits/stdc++.h>
using namespace std;
#define ALL(x) begin(x),end(x)
#define rep(i,n) for(int i=0;i<(n);i++)
#define debug(v) cout<<#v<<":";for(auto x:v){cout<<x<<' ';}cout<<endl;
#define mod 1000000007
using ll=long long;
const int INF=1000000000;
const ll LINF=1001002003004005006ll;
int dx[]={1,0,-1,0},dy[]={0,1,0,-1};
// ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}

struct IOSetup{
    IOSetup(){
        cin.tie(0);
        ios::sync_with_stdio(0);
        cout<<fixed<<setprecision(12);
    }
} iosetup;
 
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==(int)v.size()?"":" ");
    return os;
}
template<typename T>
istream &operator>>(istream &is,vector<T>&v){
    for(T &x:v)is>>x;
    return is;
}




signed main(){
    int n,m;ll t;cin>>n>>m>>t;
    using M=vector<vector<int>>;
    using V=vector<int>;
    M g(n,vector<int>(n,0));
    rep(i,m){
        int u,v;cin>>u>>v;
        g[u][v]=1;
    }    

    auto f=[&](M a,M b){
        M ret(n,V(n,0));
        rep(k,n){
            rep(i,n){
                rep(j,n){
                    if(a[i][k] and b[k][j]) ret[i][j]=1;
                }
            }
        }
        return ret;
    };

    V unko(n,0);
    unko[0]=1;
    while(t){
        if(t&1){
            V nx(n,0);
            rep(i,n)rep(j,n){
                if(unko[i] and g[i][j]) nx[j]=1;
            }
            swap(unko,nx);
        }

        g=f(g,g);
        t/=2;
    }
    int res=0;
    for(auto x:unko) res+=x;
    cout<<res<<endl;
    return 0;
}