#include <bits/stdc++.h>

using namespace std;

const int OO = 1e9;
const double EPS = 1e-9;

#define ndl cout << '\n'
#define sz(v) int(v.size())
#define pb push_back
#define mp make_pair
#define fs first
#define sc second
#define present(a, x) (a.find(x) != a.end())
#ifdef LOCAL
#define db(...) ({cout << "> Line " << __LINE__  \
		<< ": "; _db(#__VA_ARGS__, __VA_ARGS__);})
#define RNG() rng()
#else
#define db(...) true
#define RNG() true
#endif

template<class T>
void _db(const char *dbStr, T e) {
	cout << dbStr << " = " << e << endl;
}
template<class T, class... L>
void _db(const char *dbStr, T e, L... r) {
  while(*dbStr != ',') cout << *dbStr++;
  cout << " = " << e << ','; _db(dbStr + 1, r...);
}
template<class S, class T>
ostream& operator<<(ostream& o, const map<S, T>& v) {
	o << "["; int i = 0;
	for (const pair<S, T>& pr : v) o << (!i++ ? "" : ", ") << "{"
	<< pr.fs << " : " << pr.sc << "}"; return o << "]";
}
template<template <class, class...> class S, class T, class... L>
ostream& operator<<(ostream& o, const S<T, L...>& v) {
	o << "["; int i = 0;
	for (const auto& e : v) o << (!i++ ? "" : ", ") << e;
	return o << "]";
}
template<class S, class T>
ostream& operator<<(ostream& o, const pair<S, T>& pr) {
	return o << "(" << pr.fs << ", " << pr.sc << ")";
}
ostream& operator<<(ostream& o, const string& s) {
	for (const char& c : s) o << c;
	return o;
}

template<class T> using V = vector<T>;
template<class T> using VV = V<V<T>>;
template<class T> using VVV = VV<V<T>>;
using ll = long long;
using pii = pair<int, int>;
using vi = V<int>;
using vii = V<pii>;
using vvi = VV<int>;
using mii = map<int, int>;
using umii = unordered_map<int, int>;
using si = set<int>;
using usi = unordered_set<int>;

const int MX = 305;
int N, M, L, Q, ans[MX][MX];
V<vii> adj(MX);



int main() {
	#ifdef LOCAL
	auto stTime = clock();
//	freopen("in.txt", "r", stdin);
	mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
	#endif
	ios::sync_with_stdio(false);
	cout.precision(10);
	cin.tie(0);

	cin >> N >> M >> L;

	for (int i = 1; i <= M; ++i) {
		int u, v, w;

		cin >> u >> v >> w;

		if (w > L)
			continue;

		adj[u].pb(mp(v, w));
		adj[v].pb(mp(u, w));
	}

	for (int src = 1; src <= N; ++src) {
		vii dist(N + 1, mp(OO, OO));
		dist[src] = mp(0, 0);
		priority_queue<pair<pii, int>, V<pair<pii, int>>, greater<pair<pii, int>>> pq;
		pq.push(mp(dist[src], src));

		while (!pq.empty()) {
			pair<pii, int> front = pq.top();
			pq.pop();
			pii d = front.fs;
			int u = front.sc;
			if (d > dist[u])
				continue;
			for (auto& pr : adj[u]) {
				int v = pr.fs, w = pr.sc;
				pii newD;
				if (d.sc + w > L)
					newD = mp(d.fs + 1, w);
				else
					newD = mp(d.fs, d.sc + w);
				if (newD < dist[v]) {
					dist[v] = newD;
					pq.push(mp(dist[v], v));
				}
			}
		}

		for (int i = 1; i <= N; ++i) {
			if (dist[i].fs == OO)
				ans[src][i] = -1;
			else
				ans[src][i] = dist[i].fs;
		}
	}


	cin >> Q;

	for (int i = 1; i <= Q; ++i) {
		int u, v;

		cin >> u >> v;

		cout << ans[u][v] << '\n';
	}



	#ifdef LOCAL
	cout << "\n\n\nExecution time: " <<
		(clock() - stTime) * 1e3 / CLOCKS_PER_SEC << " ms" << endl;
	#endif
    return 0;
}


Measured memory_bytes: 2048