#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 < template < typename ... > class Tuple,  typename... Args, std::size_t ... Inds, std::size_t = std::tuple_size< Tuple < Args ... > >::value >
std::istream& tuple_input_impl(std::istream& os, Tuple<Args...>& tuple, std::integer_sequence<std::size_t, Inds...>)
  { (void)std::initializer_list<int>{((void)(os >> std::get< Inds >(tuple)), 0)...}; return os; }
template < template < typename ... > class Tuple,  typename... Args, std::size_t = std::tuple_size< Tuple < Args ... > >::value >
std::istream& operator>> (std::istream& os, Tuple<Args...>& tuple)
  { return tuple_input_impl(os, tuple, std::index_sequence_for<Args...>()); }

template < template < typename ... > class Tuple,  typename... Args, std::size_t ... Inds, std::size_t = std::tuple_size< Tuple < Args ... > >::value >
std::ostream& tuple_output_impl(std::ostream& os, const Tuple<Args...>& tuple, std::integer_sequence<std::size_t, Inds...>)
  { os << "("; (void)std::initializer_list<int>{((void)(os << (Inds > 0 ? "," : "") << std::get< Inds >(tuple)), 0)...}; return os << ")"; }
template < template < typename ... > class Tuple,  typename... Args, std::size_t = std::tuple_size< Tuple < Args ... > >::value >
std::ostream& operator<< (std::ostream& os, const Tuple<Args...>& tuple)
 { return tuple_output_impl(os, tuple, std::index_sequence_for<Args...>()); }
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 < typename Value >
auto dijkstra(std::vector< std::vector< std::pair< int, Value > > > const & graph, int start, Value inf) {
  std::vector< Value > dist(graph.size(), inf);
  std::priority_queue< std::pair< Value, int >,
    std::vector< std::pair< Value, int > >,
    std::greater< std::pair< Value, int > > > que;
  que.emplace(0, start);
  while (!que.empty()) {
    Value d; int crr; std::tie(d, crr) = que.top(); que.pop();
    if (dist.at(crr) <= d) continue;
    dist.at(crr) = d;
    for (auto pair : graph.at(crr)) {
      Value cost; int nxt; std::tie(nxt, cost) = pair;
      if (dist.at(nxt) - d <= cost) continue;
      que.emplace(d + cost, nxt);
    }
  }
  return dist;
}

int main() {
  std::cin.tie(0); std::cin.sync_with_stdio(false);
  int n, m, l;
  std::cin >> n >> m >> l;
  auto inf = std::make_pair(1 << 30, 0);
  auto graph = make_vector< 2, std::pair< int, int > >(n, 0);
  loop(m) {
    int u, v, x;
    std::cin >> u >> v >> x;
    u--, v--;
    if (l < x) continue;
    graph.at(u).emplace_back(v, x);
    graph.at(v).emplace_back(u, x);
  }
  // debug(graph);

  auto add = [l] (auto p, auto y) {
    assert(y <= l);
    int k, x; std::tie(k, x) = p;
    return x + y <= l
      ? std::make_pair(k, x + y)
      : std::make_pair(k + 1, y);
  };

  using Value = std::pair< int, int >;
  auto dist = make_vector< 2, Value >(n, n, inf);
  rep(start, 0, n) {
    auto & v = dist.at(start);
    std::priority_queue< std::pair< Value, int >,
      std::vector< std::pair< Value, int > >,
      std::greater< std::pair< Value, int > > > que;
    que.emplace(std::make_pair(0, 0), start);
    while (!que.empty()) {
      Value d; int crr; std::tie(d, crr) = que.top(); que.pop();
      if (v.at(crr) <= d) continue;
      v.at(crr) = d;
      for (auto pair : graph.at(crr)) {
        int cost, nxt; std::tie(nxt, cost) = pair;
        if (v.at(nxt) <= add(d, cost)) continue;
        que.emplace(add(d, cost), nxt);
      }
    }
  }
  // debug(dist);

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


Measured memory_bytes: 3568