#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define rep(x, s, t) for(llint (x) = (s); (x) <= (t); (x)++) #define chmin(x, y) (x) = min((x), (y)) #define chmax(x, y) (x) = max((x), (y)) #define all(x) (x).begin(),(x).end() #define inf 1e18 using namespace std; typedef long long llint; typedef long long ll; typedef pair P; ll mod; struct Matrix{ int h, w; vector mat; Matrix(){ h = w = 0; } Matrix(int h, int w){ this->h = h, this->w = w; mat.resize(h*w); } llint& at(int i, int j){ return mat[w*(i-1)+(j-1)]; } static Matrix ident(int size){ Matrix ret(size, size); for(int i = 1; i <= size; i++) ret.at(i, i) = 1; return ret; } Matrix operator*(Matrix& ope){ Matrix ret(h, ope.w); for(int i = 1; i <= h; i++){ for(int j = 1; j <= ope.w; j++){ for(int k = 1; k <= w; k++){ ret.at(i, j) += at(i, k) * ope.at(k, j) % mod; ret.at(i, j) %= mod; } } } return ret; } Matrix pow(llint n){ if(n == 0) return ident(h); if(n % 2){ return pow(n-1) * (*this); } else{ Matrix tmp = pow(n/2); return tmp * tmp; } } void print(){ for(int i = 1; i <= h; i++){ for(int j = 1; j <= w; j++){ cout << at(i, j) << " "; } cout << endl; } } }; ll n, m, t; Matrix mat; bool used[105]; int main(void) { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> m >> t; mat = Matrix(n, n); ll u, v; rep(i, 1, m){ cin >> u >> v; u++, v++; mat.at(v, u)++; } Matrix pmat; /*mod = 1000000007; Matrix pmat = mat.pow(t); rep(i, 1, n) if(pmat.at(i, 1)) used[i] = true;*/ mod = 998244353; pmat = mat.pow(t); rep(i, 1, n) if(pmat.at(i, 1)) used[i] = true; mod = 924844033; pmat = mat.pow(t); rep(i, 1, n) if(pmat.at(i, 1)) used[i] = true; ll ans = 0; rep(i, 1, n) if(used[i]) ans++; cout << ans << endl; return 0; }