#include <bits/stdc++.h>
#define loop(n) for (int ngtkana_is_genius = 0; ngtkana_is_genius < int(n); ngtkana_is_genius++)
#define rep(i, begin, end) for(int i = int(begin); i < int(end); i++)
#define all(v) v.begin(), v.end()
#define rand(l, r) std::uniform_int_distribution<>(l, r)(mt)
using lint = long long;
auto mt = std::mt19937_64(std::random_device{}());
auto cmn = [](auto& a, auto b){if (a > b) {a = b; return true;} return false;};
auto cmx = [](auto& a, auto b){if (a < b) {a = b; return true;} return false;};
void debug_impl() { std::cerr << std::endl; }
template <typename Head, typename... Tail>
void debug_impl(Head head, Tail... tail){
  std::cerr << " " << head;
  debug_impl(tail...);
}
#ifndef STOPIT
#define debug(...)\
  std::cerr << std::boolalpha << "[" << #__VA_ARGS__ << "]:";\
  debug_impl(__VA_ARGS__);\
  std::cerr << std::noboolalpha;
#else
#define debug 0;
#endif

template < typename Container, typename Value = typename Container::value_type, std::enable_if_t<!std::is_same< Container, std::string >::value, std::nullptr_t> = nullptr>
std::istream& operator>> (std::istream& is, Container& v)
  { for (auto & x : v) { is >> x; } return is; }

template < typename Container, typename Value = typename Container::value_type, std::enable_if_t<!std::is_same< Container, std::string >::value, std::nullptr_t> = nullptr >
std::ostream& operator<< (std::ostream& os, Container const& v) {
 os << "{";
  for (auto it = v.begin(); it != v.end(); it++)
    {os << (it != v.begin() ? "," : "") << *it;}
  return os << "}";
}

template <typename T>
auto make_vector_impl(size_t sz, T t) {return std::vector<T>(sz, t);}

template <size_t N, typename T, typename U, std::enable_if_t<N == 1, std::nullptr_t> = nullptr>
auto make_vector(size_t sz, U u) {return make_vector_impl(sz, T(u));}

template <size_t N, typename T, std::enable_if_t<N == 1, std::nullptr_t> = nullptr>
auto make_vector(size_t sz) {return std::vector<T>(sz);}

template <size_t N, typename T, typename... Args, std::enable_if_t<N != 1, std::nullptr_t> = nullptr>
auto make_vector(size_t a, Args... args) {return make_vector_impl(a, make_vector<N - 1, T>(args...));}

template <typename T, typename Size_t>
auto& at(T& t, Size_t i) {return t.at(i);}

template <typename T, typename Size_t, typename... Args>
auto& at(T& t, Size_t i, Args... args) {return at(t.at(i), args...);}

template < class Value >
auto floyd_warshall(std::vector< std::vector< Value > > adj, Value inf) {
  assert(inf <= std::numeric_limits< Value >::max() / 2);
  int n = adj.size();
  for (auto k = 0; k < n; k++) {
    for (auto i = 0; i < n; i++) {
      for (auto j = 0; j < n; j++) {
        auto & crr = adj.at(i).at(j);
        auto x = adj.at(i).at(k);
        auto y = adj.at(k).at(j);
        if (x < inf && y < inf) {
          crr = std::min(crr, x + y);
        }
      }
    }
  }
  return adj;
}

int main() {
  std::cin.tie(0); std::cin.sync_with_stdio(false);
  auto inf = std::numeric_limits< lint >::max() / 2;
  int n, m, l;
  std::cin >> n >> m >> l;
  auto adj = make_vector< 2, lint >(n, n, inf);
  rep(i, 0, n) at(adj, i, i) = 0;
  loop(m) {
    int a, b, c;
    std::cin >> a >> b >> c;
    a--, b--;
    at(adj, a, b) = c;
    at(adj, b, a) = c;
  }
  adj = floyd_warshall(adj, inf);

  auto bdj = make_vector< 2, lint > (n, n, inf);
  rep(i, 0, n) at(bdj, i, i) = 0;
  rep(i, 0, n) rep(j, 0, n) {
    if (i == j) continue;
    if (at(adj, i, j) <= l) {
      at(bdj, i, j) = 1;
    }
  }
  bdj = floyd_warshall(bdj, inf);

  int q; std::cin >> q;
  loop(q) {
    int u, v; std::cin >> u >> v;
    u--, v--;
    auto ret = at(bdj, u, v);
    ret = ret == inf ? -1 : ret - 1;
    std::cout << ret << std::endl;
  }
  return 0;
}


Measured memory_bytes: 2688