#include <bits/stdc++.h>
using namespace std;
const long long MOD=1000000007;
// const long long MOD=998244353;
#define LOCAL
#pragma region Macros
typedef long long ll;
typedef __int128_t i128;
typedef unsigned int uint;
typedef unsigned long long ull;
#define ALL(x) (x).begin(),(x).end()
const int INF=1e9;
const long long IINF=1e18;
const int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1};
const char dir[4]={'D','R','U','L'};

template<typename T>
istream &operator>>(istream &is,vector<T> &v){
    for (T &x:v) is >> x;
    return is;
}
template<typename T>
ostream &operator<<(ostream &os,const vector<T> &v){
    for (int i=0;i<v.size();++i){
        os << v[i] << (i+1==v.size()?"": " ");
    }
    return os;
}
template<typename T,typename U>
ostream &operator<<(ostream &os,const pair<T,U> &p){
    os << '(' << p.first << ',' << p.second << ')';
    return os;
}
template<typename T,typename U,typename V>
ostream&operator<<(ostream &os,const tuple<T,U,V> &t){
    os << '(' << get<0>(t) << ',' << get<1>(t) << ',' << get<2>(t) << ')';
    return os;
}
template<typename T,typename U,typename V,typename W>
ostream&operator<<(ostream &os,const tuple<T,U,V,W> &t){
    os << '(' << get<0>(t) << ',' << get<1>(t) << ',' << get<2>(t) << ',' << get<3>(t) << ')';
    return os;
}
template<typename T,typename U>
ostream &operator<<(ostream &os,const map<T,U> &m){
    os << '{';
    for (auto itr=m.begin();itr!=m.end();){
        os << '(' << itr->first << ',' << itr->second << ')';
        if (++itr!=m.end()) os << ',';
    }
    os << '}';
    return os;
}
template<typename T,typename U>
ostream &operator<<(ostream &os,const unordered_map<T,U> &m){
    os << '{';
    for (auto itr=m.begin();itr!=m.end();){
        os << '(' << itr->first << ',' << itr->second << ')';
        if (++itr!=m.end()) os << ',';
    }
    os << '}';
    return os;
}
template<typename T>
ostream &operator<<(ostream &os,const set<T> &s){
    os << '{';
    for (auto itr=s.begin();itr!=s.end();){
        os << *itr;
        if (++itr!=s.end()) os << ',';
    }
    os << '}';
    return os;
}
template<typename T>
ostream &operator<<(ostream &os,const multiset<T> &s){
    os << '{';
    for (auto itr=s.begin();itr!=s.end();){
        os << *itr;
        if (++itr!=s.end()) os << ',';
    }
    os << '}';
    return os;
}
template<typename T>
ostream &operator<<(ostream &os,const unordered_set<T> &s){
    os << '{';
    for (auto itr=s.begin();itr!=s.end();){
        os << *itr;
        if (++itr!=s.end()) os << ',';
    }
    os << '}';
    return os;
}
template<typename T>
ostream &operator<<(ostream &os,const deque<T> &v){
    for (int i=0;i<v.size();++i){
        os << v[i] << (i+1==v.size()?"": " ");
    }
    return os;
}

void debug_out(){cerr << '\n';}
template<class Head,class... Tail>
void debug_out(Head&& head,Tail&&... tail){
    cerr << head;
    if (sizeof...(Tail)>0) cerr << ", ";
    debug_out(move(tail)...);
}
#ifdef LOCAL
#define debug(...) cerr << " ";\
cerr << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << '\n';\
cerr << " ";\
debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

template<typename T> T gcd(T x,T y){return y!=0?gcd(y,x%y):x;}
template<typename T> T lcm(T x,T y){return x/gcd(x,y)*y;}

template<class T1,class T2> inline bool chmin(T1 &a,T2 b){
    if (a>b){a=b; return true;} return false;
}
template<class T1,class T2> inline bool chmax(T1 &a,T2 b){
    if (a<b){a=b; return true;} return false;
}
#pragma endregion

template<uint32_t mod> class modint{
    using i64=int64_t;
    using u32=uint32_t;
    using u64=uint64_t;
public:
    u32 v;
    constexpr modint(const i64 x=0) noexcept :v(x<0?mod-1-(-(x+1)%mod):x%mod){}
    constexpr u32 &value() noexcept {return v;}
    constexpr const u32 &value() const noexcept {return v;}
    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 {
        v+=rhs.v;
        if (v>=mod) v-=mod;
        return *this;
    }
    constexpr modint &operator-=(const modint &rhs) noexcept {
        if (v<rhs.v) v+=mod;
        v-=rhs.v;
        return *this;
    }
    constexpr modint &operator*=(const modint &rhs) noexcept {
        v=(u64)v*rhs.v%mod;
        return *this;
    }
    constexpr modint &operator/=(const modint &rhs) noexcept {
        return *this*=rhs.pow(mod-2);
    }
    constexpr modint pow(u64 exp) const noexcept {
        modint self(*this),res(1);
        while (exp>0){
            if (exp&1) res*=self;
            self*=self; exp>>=1;
        }
        return res;
    }
    constexpr modint &operator++() noexcept {if (++v==mod) v=0; return *this;}
    constexpr modint &operator--() noexcept {if (v==0) v=mod; return --v,*this;}
    constexpr modint operator++(int) noexcept {modint t=*this; return ++*this,t;}
    constexpr modint operator--(int) noexcept {modint t=*this; return --*this,t;}
    constexpr modint operator-() const noexcept {return modint(mod-v);}
    template<class T> friend constexpr modint operator+(T x,modint y) noexcept {return modint(x)+y;}
    template<class T> friend constexpr modint operator-(T x,modint y) noexcept {return modint(x)-y;}
    template<class T> friend constexpr modint operator*(T x,modint y) noexcept {return modint(x)*y;}
    template<class T> friend constexpr modint operator/(T x,modint y) noexcept {return modint(x)/y;}
    constexpr bool operator==(const modint &rhs) const noexcept {return v==rhs.v;}
    constexpr bool operator!=(const modint &rhs) const noexcept {return v!=rhs.v;}
    constexpr bool operator!() const noexcept {return !v;}
    friend istream &operator>>(istream &s,modint &rhs) noexcept {
        i64 v; rhs=modint{(s>>v,v)}; return s;
    }
    friend ostream &operator<<(ostream &s,const modint &rhs) noexcept {
        return s<<rhs.v;
    }
};

template<class T,size_t N>
struct SquareMatrix{
    array<array<T,N>,N> A;
    SquareMatrix()=default;
    size_t size() {return N;}
    inline const array<T,N> &operator[](int i) const {return A[i];}
    inline array<T,N> &operator[](int i){return A[i];}
    static SquareMatrix add_identity(){
        return SquareMatrix();
    }
    static SquareMatrix mul_identity(){
        SquareMatrix res;
        for (size_t i=0;i<N;++i) res[i][i]=1;
        return res;
    }
    SquareMatrix operator+(const SquareMatrix &B) const {return SquareMatrix(*this)+=B;}
    SquareMatrix operator-(const SquareMatrix &B) const {return SquareMatrix(*this)-=B;}
    SquareMatrix operator*(const SquareMatrix &B) const {return SquareMatrix(*this)*=B;}
    SquareMatrix operator^(const long long &k) const {return SquareMatrix(*this)^=k;}
    SquareMatrix &operator+=(const SquareMatrix &B){
        for (size_t i=0;i<N;++i){
            for (size_t j=0;j<N;++j){
                (*this)[i][j]+=B[i][j];
            }
        }
        return *this;
    }
    SquareMatrix &operator-=(const SquareMatrix &B){
        for (size_t i=0;i<N;++i){
            for (size_t j=0;j<N;++j){
                (*this)[i][j]-=B[i][j];
            }
        }
        return *this;
    }
    SquareMatrix &operator*=(const SquareMatrix &B){
        array<array<T,N>,N> C;
        for (size_t i=0;i<N;++i){
            for (size_t j=0;j<N;++j){
                for (size_t k=0;k<N;++k){
                    C[i][j]+=(*this)[i][k]*B[k][j];
                }
            }
        }
        A.swap(C);
        return *this;
    }
    SquareMatrix &operator^=(long long k){
        SquareMatrix res=SquareMatrix::mul_identity();
        while (k>0){
            if (k&1) res*=*this;
            *this*=*this; k>>=1LL;
        }
        A.swap(res.A);
        return *this;
    }
};

const int MAX_N=110;
using mint=modint<MOD>;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int N,M; ll T; cin >> N >> M >> T;
    SquareMatrix<mint,MAX_N> SM;
    for (int i=0;i<M;++i){
        int a,b; cin >> a >> b;
        SM[a][b]=1;
    }
    SM^=T;
    int ans=0;
    for (int i=0;i<N;++i) ans+=(SM[0][i]!=0);

    cout << ans << '\n';
}