Language: C++

#include <cassert>
#include <cstdio>
#include <cmath>
#include <iostream>
#include <iomanip>
#include <sstream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <numeric>
#include <algorithm>

using namespace std;
using lint = long long;
constexpr int MOD = 1000000007, INF = 1010101010;
constexpr lint LINF = 1LL << 60;

template <class T>
ostream &operator<<(ostream &os, const vector<T> &vec) {
	for (const auto &e : vec) os << e << (&e == &vec.back() ? "\n" : " ");
	return os;
}

template <class T>
ostream &operator<<(ostream &os, const set<T> &st) {
	for (const auto &e : st) os << e << " ";
	return os;
}

template <class T1, class T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
	os << "(" << p.first << "," << p.second << ")";
	return os;
}

template <class T1, class T2>
ostream &operator<<(ostream &os, const map<T1, T2> &mp) {
	for (const auto &e : mp) os << e << " ";
	return os;
}

#ifdef _DEBUG
template <class T>
void dump(const char* str, T &&h) { cerr << str << " = " << h << "\n"; };
template <class Head, class... Tail>
void dump(const char* str, Head &&h, Tail &&... t) {
	while (*str != ',') cerr << *str++; cerr << " = " << h << "\n";
	dump(str + (*(str + 1) == ' ' ? 2 : 1), t...);
}
#define DMP(...) dump(#__VA_ARGS__, __VA_ARGS__)
#else 
#define DMP(...) ((void)0)
#endif

template<class T = lint>
struct Edge {
	int to;
	T cost;
	int tank;
	Edge() {}
	Edge(int to, T cost, int tank = 0) : to(to), cost(cost), tank(tank) {}
	bool operator>(const Edge &r) const { return this->cost > r.cost; }
};

int main() {

	cin.tie(nullptr);
	ios::sync_with_stdio(false);

	int N, M, L;
	cin >> N >> M >> L;

	vector<vector<Edge<int>>> edges(N);
	for (int i = 0; i < M; i++) {
		int u, v, len;
		cin >> u >> v >> len;
		u--, v--;
		edges[u].emplace_back(v, len);
		edges[v].emplace_back(u, len);
	}

	auto bfs = [&](int st) {
		vector<pair<int, int>> dp(N, { INF, 0 });
		dp[st] = { 0, -L };
		queue<pair<pair<int, int>, int>> que;
		que.emplace(st, dp[st]);
		while (!que.empty()) {
			auto now = que.front();
			que.pop();
			for (const auto &e : edges[now.second]) {

				if (e.cost > L || now.first > dp[e.to]) continue;

				auto tmp = now.first;
				if (e.cost > -tmp.second) {
					tmp.first++;
					tmp.second = -L + e.cost;
				}
				else tmp.second += e.cost;

				if (tmp < dp[e.to]) {
					dp[e.to] = tmp;
					que.emplace(e.to, tmp);
				}

			}
		}
		return move(dp);
	};

	vector<vector<pair<int, int>>> memo(N);
	for (int i = 0; i < N; i++) memo[i] = bfs(i);

	int Q;
	cin >> Q;
	for (int i = 0; i < Q; i++) {
		int s, t;
		cin >> s >> t;
		s--, t--;
		auto tmp = memo[s][t].first;
		if (tmp != INF) cout << tmp << "\n";
		else cout << -1 << "\n";
	}

	return 0;
}

Compiler output:
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/c++allocator.h:33,
                 from /usr/include/c++/14/bits/allocator.h:46,
                 from /usr/include/c++/14/string:43,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:4:
/usr/include/c++/14/bits/new_allocator.h: In instantiation of 'void std::__new_allocator<_Tp>::construct(_Up*, _Args&& ...) [with _Up = std::pair<std::pair<int, int>, int>; _Args = {int&, std::pair<int, int>&}; _Tp = std::pair<std::pair<int, int>, int>]':
/usr/include/c++/14/bits/alloc_traits.h:575:17:   required from 'static void std::allocator_traits<std::allocator<_CharT> >::construct(allocator_type&, _Up*, _Args&& ...) [with _Up = std::pair<std::pair<int, int>, int>; _Args = {int&, std::pair<int, int>&}; _Tp = std::pair<std::pair<int, int>, int>; allocator_type = std::allocator<std::pair<std::pair<int, int>, int> >]'
  575 |           __a.construct(__p, std::forward<_Args>(__args)...);
      |           ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/deque.tcc:170:30:   required from 'std::deque<_Tp, _Alloc>::reference std::deque<_Tp, _Alloc>::emplace_back(_Args&& ...) [with _Args = {int&, std::pair<int, int>&}; _Tp = std::pair<std::pair<int, int>, int>; _Alloc = std::allocator<std::pair<std::pair<int, int>, int> >; reference = std::pair<std::pair<int, int>, int>&]'
  170 |             _Alloc_traits::construct(this->_M_impl,
      |             ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
  171 |                                      this->_M_impl._M_finish._M_cur,
      |                                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  172 |                                      std::forward<_Args>(__args)...);
      |                                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_queue.h:295:25:   required from 'decltype(auto) std::queue<_Tp, _Sequence>::emplace(_Args&& ...) [with _Args = {int&, std::pair<int, int>&}; _Tp = std::pair<std::pair<int, int>, int>; _Sequence = std::deque<std::pair<std::pair<int, int>, int>, std::allocator<std::pair<std::pair<int, int>, int> > >]'
  295 |         { return c.emplace_back(std::forward<_Args>(__args)...); }
      |                  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a.cc:87:14:   required from here
   87 |                 que.emplace(st, dp[st]);
      |                 ~~~~~~~~~~~^~~~~~~~~~~~
/usr/include/c++/14/bits/new_allocator.h:191:11: error: no matching function for call to 'std::pair<std::pair<int, int>, int>::pair(int&, std::pair<int, int>&)'
  191 |         { ::new((void *)__p) _Up(std::forward<_Args>(__args)...); }
      |           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/bits/specfun.h:43,
                 from /usr/include/c++/14/cmath:3906,
                 from a.cc:3:
/usr/include/c++/14/bits/stl_pair.h:913:28: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(std::_PCC<((! std::is_same<std::pair<int, int>, _U1>::value) || (! std::is_same<int, _U2>::value)), std::pair<int, int>, int>::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<((! std::is_same<std::pair<int, int>, _U1>::value) || (! std::is_same<int, _U2>::value)), std::pair<int, int>, int>::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(std::pair<_U1, _U2>&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  913 |         explicit constexpr pair(pair<_U1, _U2>&& __p)
      |                            ^~~~
/usr/include/c++/14/bits/stl_pair.h:913:28: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_pair.h:902:19: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(std::_PCC<((! std::is_same<std::pair<int, int>, _U1>::value) || (! std::is_same<int, _U2>::value)), std::pair<int, int>, int>::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<((! std::is_same<std::pair<int, int>, _U1>::value) || (! std::is_same<int, _U2>::value)), std::pair<int, int>, int>::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(std::pair<_U1, _U2>&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<((! std::is_same<_T1, _U1>::value) || (! std::is_same<_T2, _U2>::value)), _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  902 |         constexpr pair(pair<_U1, _U2>&& __p)
      |                   ^~~~
/usr/include/c++/14/bits/stl_pair.h:902:19: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_pair.h:891:28: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(_MoveConstructiblePair<_U1, _U2>() && (! _ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, _U2&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<true, _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && (! std::_PCC<true, _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>())), bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  891 |         explicit constexpr pair(_U1&& __x, _U2&& __y)
      |                            ^~~~
/usr/include/c++/14/bits/stl_pair.h:891:28: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:890:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  890 |                          bool>::type=false>
      |                                      ^~~~~
/usr/include/c++/14/bits/stl_pair.h:881:19: note: candidate: 'template<class _U1, class _U2, typename std::enable_if<(_MoveConstructiblePair<_U1, _U2>() && _ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, _U2&&) [with _U2 = _U1; typename std::enable_if<(std::_PCC<true, _T1, _T2>::_MoveConstructiblePair<_U1, _U2>() && std::_PCC<true, _T1, _T2>::_ImplicitlyMoveConvertiblePair<_U1, _U2>()), bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  881 |         constexpr pair(_U1&& __x, _U2&& __y)
      |                   ^~~~
/usr/include/c++/14/bits/stl_pair.h:881:19: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:880:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  880 |                          bool>::type=true>
      |                                      ^~~~
/usr/include/c++/14/bits/stl_pair.h:869:9: note: candidate: 'template<class _U2, typename std::enable_if<std::__and_<std::is_pointer<std::pair<int, int> >, std::__not_<std::is_reference<_Tp> >, std::is_constructible<int, _U1>, std::__not_<std::is_constructible<int, const _U1&> >, std::__not_<std::is_convertible<_U1, int> > >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(__zero_as_null_pointer_constant, _U2&&, ...) [with typename std::enable_if<std::__and_<std::is_pointer<_Tp>, std::__not_<std::is_reference<_U1> >, std::is_constructible<_T2, _U2>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::__not_<std::is_convertible<_U2, _T2> > >::value, bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  869 |         pair(__zero_as_null_pointer_constant, _U2&& __y, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:869:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:866:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  866 |                              bool> = false>
      |                                      ^~~~~
/usr/include/c++/14/bits/stl_pair.h:856:9: note: candidate: 'template<class _U2, typename std::enable_if<std::__and_<std::is_pointer<std::pair<int, int> >, std::__not_<std::is_reference<_Tp> >, std::is_constructible<int, _U1>, std::__not_<std::is_constructible<int, const _U1&> >, std::is_convertible<_U1, int> >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(__zero_as_null_pointer_constant, _U2&&, ...) [with typename std::enable_if<std::__and_<std::is_pointer<_Tp>, std::__not_<std::is_reference<_U1> >, std::is_constructible<_T2, _U2>, std::__not_<std::is_constructible<_T1, const _U1&> >, std::is_convertible<_U2, _T2> >::value, bool>::type <anonymous> = _U2; _T1 = std::pair<int, int>; _T2 = int]'
  856 |         pair(__zero_as_null_pointer_constant, _U2&& __y, ...)
      |         ^~~~
/usr/include/c++/14/bits/stl_pair.h:856:9: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_pair.h:853:38: error: no type named 'type' in 'struct std::enable_if<false, bool>'
  853 |                              bool> = true>
      |                                      ^~~~
/usr/include/c++/14/bits/stl_pair.h:843:9: note: candidate: 'template<class _U1, typename std::enable_if<std::__and_<std::__not_<std::is_reference<_Tp> >, std::is_pointer<int>, std::is_constructible<std::pair<int, int>, _U1>, std::__not_<std::is_constructible<std::pair<int, int>, const _U1&> >, std::__not_<std::is_convertible<_U1, std::pair<int, int> > > >::value, bool>::type <anonymous> > constexpr std::pair<_T1, _T2>::pair(_U1&&, __zero_as_null_pointer_constant, ...) [with typename std::enable_if<std::__and_<std::__not_<std::is_reference<_U1> >, std::is_pointer<_T2>, std::is_constructible<_T1, _U1>, std::__not_<std::is_constructible<_T1, const