#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <stack>
#include <queue>
#include <bitset>
#include <numeric>
#include <cassert>
#ifdef DEBUG
#include "./Lib/debug.hpp"
#include "./Lib/Timer.hpp"
#include "./Lib/sample.hpp"
#else
#define dump(...)
template<class T>constexpr inline auto d_val(T a, T b) { return a; }
#endif

/* (=＾o＾=) */
#define int ll

/* macro */
#define FOR(i, b, e) for(ll i = (ll)(b); i < (ll)(e); ++i)
#define RFOR(i, b, e) for(ll i = (ll)(e-1); i >= (ll)(b); --i)
#define REP(i, n) FOR(i, 0, n)
#define RREP(i, n) RFOR(i, 0, n)
#define REPC(x,c) for(const auto& x:(c))
#define REPI2(it,b,e) for(auto it = (b); it != (e); ++it)
#define REPI(it,c) REPI2(it, (c).begin(), (c).end())
#define RREPI(it,c) REPI2(it, (c).rbegin(), (c).rend())
#define REPI_ERACE2(it, b, e) for(auto it = (b); it != (e);)
#define REPI_ERACE(it, c) REPI_ERACE2(it, (c).begin(), (c).end())
#define ALL(x) (x).begin(),(x).end()
#define cauto const auto&
/* macro func */
template<class T>
inline auto sort(T& t) { std::sort(ALL(t)); }
template<class T>
inline auto rsort(T& t) { std::sort((t).rbegin(), (t).rend()); }
template<class T>
inline auto unique(T& t) { (t).erase(unique((t).begin(), (t).end()), (t).end()); }
template<class T, class S>
inline auto chmax(T& t, const S& s) { if (s > t) { t = s; return true; } return false; }
template<class T, class S>
inline auto chmaxE(T& t, const S& s) { if (s >= t) { t = s; return true; } return false; }
template<class T, class S>
inline auto chmin(T& t, const S& s) { if (s < t) { t = s; return true; } return false; }
inline auto BR() { std::cout << "\n"; }

/* type define */
using ll = long long;
using PAIR = std::pair<ll, ll>;
using VS = std::vector<std::string>;
using VL = std::vector<long long>;
using VVL = std::vector<VL>;
using VVVL = std::vector<VVL>;
using VD = std::vector<double>;
template<class T>
using V = std::vector<T>;

/* using std */
using std::cout;
constexpr char endl = '\n';
using std::cin;
using std::pair;
using std::string;
using std::stack;
using std::queue;
using std::vector;
using std::list;
using std::map;
using std::unordered_map;
using std::multimap;
using std::unordered_multimap;
using std::set;
using std::unordered_set;
using std::unordered_multiset;
using std::multiset;
using std::bitset;
using std::priority_queue;

/* constant value */
constexpr ll MOD = 1000000007;
//constexpr ll MOD = 998244353;

/* Initial processing  */
struct Preprocessing { Preprocessing() { std::cin.tie(0); std::ios::sync_with_stdio(0); }; }_Preprocessing;

/* Remove the source of the bug */
inline signed pow(signed, signed) { assert(false); return -1; }

/* define hash */
namespace std { template <>	class hash<std::pair<ll, ll>> { public:	size_t operator()(const std::pair<ll, ll>& x) const { return hash<ll>()(1000000000 * x.first + x.second); } }; }

/* input */
template<class T> std::istream& operator >> (std::istream& is, vector<T>& vec) { for (T& x : vec) is >> x; return is; }

//=============================================================================================


auto dijkstra(const unordered_multimap<ll, PAIR>& graph, ll n, ll begin, ll l) {
	V<PAIR> cost(n, {1e15,1e15});
	cost[begin] = {0,0};

	using TYPE= pair<PAIR, ll>;
	priority_queue<TYPE, vector<TYPE>, std::greater<TYPE>> q;
	q.emplace(PAIR{0,0}, begin);
	while (!q.empty()) {
		ll from = q.top().second;
		ll nowNum = q.top().first.first;
		ll nowL = q.top().first.second;
		q.pop();
		if (cost[from] < PAIR{nowNum, nowL}) { continue; }
		auto range = graph.equal_range(from);
		REPI2(itr, range.first, range.second) {
			ll to = itr->second.first;
			ll c = itr->second.second;
			if (c > l) { continue; }
			ll nx = nowNum;
			ll nxL = nowL;
			if (nowL + c > l) {
				nxL = 0;
				++nx;
			}
			nxL += c;
			if (PAIR{nx,nxL} < cost[to]) {
				cost[to] = PAIR{nx,nxL};
				q.emplace(cost[to], to);
			}
		}
	}
	return cost;
}

signed main() {
	ll n, m, l;
	cin >> n >> m >> l;
	unordered_multimap<ll, PAIR> graph;
	REP(_, m) {
		ll a, b, c;
		cin >> a >> b >> c;
		--a; --b;
		graph.emplace(a, PAIR{b,c});
		graph.emplace(b, PAIR{a,c});
	}

	V<V<PAIR>> ans; ans.reserve(n);
	REP(i, n) {
		auto cost = dijkstra(graph, n, i, l);
		ans.emplace_back(cost);
	}
	dump(ans);
	ll q;
	cin >> q;
	REP(_, q) {
		ll a, b;
		cin >> a >> b;
		--a; --b;
		ll val = ans[a][b].first;
		if (val > 1e14) { val = -1; }
		cout << val << endl;
	}
}


Measured memory_bytes: 8380