//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx")
//#undef LOCAL
#include <bits/stdc++.h>

using namespace std;
using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;
constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n - 1); }
template <class T> using V = vector<T>;
template <class T> using VV = V<V<T>>;

#ifdef LOCAL
struct PrettyOS {
    ostream& os;
    bool first;
    template <class T> auto operator<<(T&& x) {
        if (!first) os << ", ";
        first = false;
        os << x;
        return *this;
    }
};
template <class... T> void dbg0(T&&... t) {
    (PrettyOS{cerr, true} << ... << t);
}
#define dbg(...)                                            \
    do {                                                    \
        cerr << __LINE__ << " : " << #__VA_ARGS__ << " = "; \
        dbg0(__VA_ARGS__);                                  \
        cerr << endl;                                       \
    } while (false);
#else
#define dbg(...)
#endif

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

template <class T> ostream& operator<<(ostream& os, const V<T>& v) {
    os << "[";
    for (auto d : v) os << d << ", ";
    return os << "]";
}

struct Scanner {
    FILE* fp = nullptr;
    char line[1 << 15];
    size_t st = 0, ed = 0;
    void reread() {
        memmove(line, line + st, ed - st);
        ed -= st;
        st = 0;
        ed += fread(line + ed, 1, (1 << 15) - ed, fp);
    }
    void succ() {
        while (true) {
            if (st == ed) reread();
            while (st != ed && isspace(line[st])) st++;
            if (st != ed) break;
        }
        if (ed - st <= 50) reread();
    }
    template <class T, enable_if_t<is_integral<T>::value, int> = 0>
    bool read_single(T& ref) {
        succ();
        bool neg = false;
        if (line[st] == '-') {
            neg = true;
            st++;
        }
        ref = T(0);
        while (isdigit(line[st])) {
            ref = 10 * ref + (line[st++] - '0');
        }
        if (neg) ref = -ref;
        return true;
    }
    void read() {}
    template <class H, class... T> void read(H& h, T&... t) {
        bool f = read_single(h);
        assert(f);
        read(t...);
    }
    Scanner(FILE* _fp) : fp(_fp) {}
};

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);
    Scanner sc(stdin);
    int n, m; ll l;
    sc.read(n, m, l);
    dbg(n, m, l);
//    cin >> n >> m >> l;

    VV<ll> di(n, V<ll>(n, TEN(18)));
    for (int i = 0; i < n; i++) {
        di[i][i] = 0;
    }
    for (int i = 0; i < m; i++) {
        int a, b; ll c;
        sc.read(a, b, c); a--; b--;
        //cin >> a >> b >> c; a--; b--;
        di[a][b] = di[b][a] = c;
    }
    for (int k = 0; k < n; k++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                di[i][j] = min(di[i][j], di[i][k] + di[k][j]);
            }
        }
    }

    VV<int> ans(n, V<int>(n, TEN(9)));
    for (int i = 0; i < n; i++) {
        ans[i][i] = 0;
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (di[i][j] <= l) ans[i][j] = 1;
        }
    }

    for (int k = 0; k < n; k++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                ans[i][j] = min(ans[i][j], ans[i][k] + ans[k][j]);
            }
        }
    }

    int q;
    sc.read(q);
    for (int i = 0; i < q; i++) {
        int x, y;
        sc.read(x, y); x--; y--;
        int a = ans[x][y] - 1;
        if (a > TEN(8)) a = -1;
        cout << a << "\n";
    }
    return 0;
}


Measured memory_bytes: 1664