#include <bits/stdc++.h>
#define endl '\n'
#define int long long
#define lint long long
#define pii pair<int,int>
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
#define SZ(v) ((int)v.size())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
#define MINF(a) memset(a,0x3f,sizeof(a))
#define POW(n) (1LL<<(n))
#define POPCNT(n) (__builtin_popcount(n))
#define IN(i,a,b) (a <= i && i <= b)
using namespace std;
template <typename T> inline bool CHMIN(T& a,T b) { if(a>b) { a=b; return 1; } return 0; }
template <typename T> inline bool CHMAX(T& a,T b) { if(a<b) { a=b; return 1; } return 0; }
template <typename T> inline void SORT(T& a) { sort(ALL(a)); }
template <typename T> inline void REV(T& a) { reverse(ALL(a)); }
template <typename T> inline void UNI(T& a) { sort(ALL(a)); a.erase(unique(ALL(a)),a.end()); }
template <typename T> inline T LB(vector<T>& v, T a) { return *lower_bound(ALL(v),a); }
template <typename T> inline int LBP(vector<T>& v, T a) { return lower_bound(ALL(v),a) - v.begin(); }
template <typename T> inline T UB(vector<T>& v, T a) { return *upper_bound(ALL(v),a); }
template <typename T> inline int UBP(vector<T>& v, T a) { return upper_bound(ALL(v),a) - v.begin(); }
template <typename T1, typename T2> ostream& operator<< (ostream& os, const pair<T1,T2>& p) { os << p.first << " " << p.second; return os; }
template <typename T1, typename T2> istream& operator>> (istream& is, pair<T1,T2>& p) { is >> p.first >> p.second; return is; }
template <typename T> ostream& operator<< (ostream& os, const vector<T>& v) { REP(i,v.size()) { if (i) os << " "; os << v[i]; } return os; }
template <typename T> istream& operator>> (istream& is, vector<T>& v) { for(T& in : v) is >> in; return is; }
template <typename T = int> vector<T> make_v(size_t a) { return vector<T>(a); }
template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) { return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...)); }
template <typename T, typename V> typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) { t = v; }
template <typename T, typename V> typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) { for(auto &e : t) fill_v(e,v); }
const lint MOD = 1000000007;
const lint INF = 0x3f3f3f3f3f3f3f3f;
const double EPS = 1e-10;

struct edge {
    int t, c;
    edge() {}
    edge(int t, int c): t(t), c(c) {}
};

int N, M, L, Q;
vector<edge> G[310];
pii dis[310][310];

void _main() {
    cin >> N >> M >> L;
    REP(i, M) {
        int A, B, C;
        cin >> A >> B >> C;
        A--; B--;
        if (C <= L) {
            G[A].emplace_back(B, C);
            G[B].emplace_back(A, C);
        }
    }

    REP(i, N) {
        REP(j, N) {
            dis[i][j] = pii(INF, INF);
        }
        dis[i][i] = pii(0, -L);

        using P = pair<pii, int>;
        priority_queue<P, vector<P>, greater<P>> que;
        que.emplace(dis[i][i], i);
        while (!que.empty()) {
            pii p;
            int v;
            tie(p, v) = que.top();
            que.pop();
            if (dis[i][v] < p) continue;
            for (edge e : G[v]) {
                int nv = e.t;
                int cost = e.c;
                pii np;
                if (-p.second < cost) {
                    np = pii(p.first + 1, -(L - cost));
                } else {
                    np = pii(p.first, -(-p.second - cost));
                }
                if (dis[i][nv] > np) {
                    dis[i][nv] = np;
                    que.emplace(np, nv);
                }
            }
        }
    }

    cin >> Q;
    REP(i, Q) {
        int s, t;
        cin >> s >> t;
        s--; t--;
        cout << (dis[s][t].first == INF ? -1 : dis[s][t].first) << endl;
    }
}

signed main(signed argc, char **argv) {
    if (argc > 1) {
        if (strchr(argv[1], 'i'))
            freopen("input.txt", "r", stdin);
        if (strchr(argv[1], 'o'))
            freopen("output.txt", "w", stdout);
    }
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    _main();
    return 0;
}

Measured memory_bytes: 4352