#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; using ull = unsigned long long; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } //template T gcd(T a, T b) { a = abs(a), b = abs(b); while (b > 0) { tie(a, b) = make_pair(b, a % b); }return a; } //mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count()); constexpr long long INF = 1LL << 60; constexpr int inf = 1000000007; //constexpr long long mod = 1000000007LL; constexpr long long mod = 998244353; int main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); int n, m; ll T; cin >> n >> m >> T; constexpr int size = 100; static array, size> mat, ret, tm; for (int i = 0; i < m; i++) { int a, b; cin >> a >> b; mat[a][b] = true; } if (T == 0) { cout << 1 << "\n"; return 0; } auto mul = [&](const array, size>& a, const array, size>& b)->array, size>{ for (int i = 0; i < size; i++) for (int j = 0; j < size; j++) tm[j][i] = b[i][j]; for (int i = 0; i < size; i++) for (int j = 0; j < size; j++) ret[i][j] = (a[i] & tm[j]).any(); return ret; }; ret = mat; T -= 1; while (T > 0) { if (T & 1) { ret = mul(ret, mat); } mat = mul(mat, mat); T >>= 1; } int res = 0; for (int i = 0; i < size; i++) res += ret[i][0]; cout << res << endl; }