#include <vector>
#include <iostream>
#include <cmath>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <fstream>
#include <unistd.h>
#include <string.h>
#include <string>
#include <numeric>
#include <queue>
#include <deque>
#include <sstream>
#include <iomanip>
#include <set>
#include <stack>
#include <cassert>
#include <functional>
#include <random>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<vvvl> vvvvl;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vvb> vvvb;
typedef vector<vvvb> vvvvb;
typedef vector<string> vs;
typedef vector<vs> vvs;
typedef vector<vvs> vvvs;
typedef vector<char> vc;
typedef vector<vector<char>> vvc;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<vvd> vvvd;
typedef pair<ll, ll> PL;
typedef vector<PL> vpl;
typedef vector<vector<PL>> vvpl;
typedef vector<vvpl> vvvpl;
const int INF = 1001001001;
const ll LINF = 1e17;
const double pi = 3.1415926535897932;
const string endstr = "\n";
#define FOR(i, a, b) for(ll i = (a); i < b; i++)
#define RFOR(i, a, b) for(ll i = (a); i > b; i--)
#define rep(i, n) for(ll i = 0; i < n; i++)
#define rrep(i, n) for(ll i = n-1; i > -1; i--)
#define FORMAP(it, m) for(auto it = m.begin(); it != m.end(); it++)
#define ff first
#define ss second
#define pb push_back
#define epb emplace_back
#define ALL(X) (X).begin(),(X).end()

template <typename T>
T gcd(T a, T b) {
    return (a == 0) ? b : gcd(b%a, a);
}
template <typename T>
T lcm(T a, T b) {
    return a / gcd(a, b) * b;
}

bool p_comp_fs(const PL p1, const PL p2){ return p1.first < p2.first;};
bool p_comp_fg(const PL p1, const PL p2){ return p1.first > p2.first;};
bool p_comp_ss(const PL p1, const PL p2){ return p1.second < p2.second;};
bool p_comp_sg(const PL p1, const PL p2){ return p1.second > p2.second;};
template <typename T>
vector<T> uniquen(vector<T> vec){
    sort(ALL(vec));
    vec.erase(unique(vec.begin(), vec.end()), vec.end());
    return vec;
}

inline ll popcnt(ll x){return __builtin_popcountll((unsigned long long)x);};
template<class T> bool chmax(T &a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, T b) { if (a > b) { a = b; return true; } return false; }
//friend bool operator<(const stc& lhs, const stc& rhs){
//    return std::tie(lhs.l, lhs.r) < std::tie(rhs.l, rhs.r);
//}



int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ll N, M, L; cin >> N >> M >> L;
    vvpl G(N);
    rep(_, M){
        ll a, b, c; cin >> a >> b >> c; a--; b--;
        if(c > L) continue;
        G[a].pb({b, c});
        G[b].pb({a, c});
    }
    
    vvpl dist(N, vpl(N, {LINF, 0}));
    
    rep(st, N){
        vpl& d = dist[st];
        d[st] = {0, -L};
        priority_queue<pair<PL, ll>, vector<pair<PL, ll>>, greater<pair<PL, ll>>> pq;
        pq.push({{0, -L}, st});
        while(!pq.empty()){
            ll now = pq.top().ss, ncnt = pq.top().ff.ff, nene = -pq.top().ff.ss;
            pq.pop();
            if(d[now].ff < ncnt) continue;
            if(d[now].ff == ncnt && -d[now].ss > nene) continue;
            for(auto to_cost : G[now]){
                ll to = to_cost.ff, cost = to_cost.ss;
                ll will_cnt = ncnt;
                ll will_ene = nene;
                if(nene - cost < 0){
                    will_cnt+=1; will_ene = L-cost;
                }
                else{
                    will_ene -= cost;
                }
                if(will_cnt < d[to].ff || (will_cnt == d[to].ff && will_ene > -d[to].ss)){
                    d[to] = {will_cnt, -will_ene};
                    pq.push({{will_cnt, -will_ene}, to});
                }
            }
        }
    }
    
    ll Q; cin >> Q;
    rep(_, Q){
        ll s, t; cin >> s >> t; s--; t--;
        ll cnt = dist[s][t].ff;
        cout << (cnt == LINF ? -1 : cnt) << endstr;
    }
    
    return 0;
}


Measured memory_bytes: 4352