#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <tuple>
#include <cstdint>
#include <cstdio>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <deque>
#include <unordered_map>
#include <unordered_set>
#include <bitset>
#include <cctype>
#include <functional>
#include <ctime>
#include <cmath>
#include <limits>
#include <numeric>
#include <type_traits>
#include <iomanip>
#include <float.h>
#include <math.h>
using namespace std;
using ll = long long;
unsigned euclidean_gcd(unsigned a, unsigned b) {
    if (a < b) return euclidean_gcd(b, a);
    unsigned r;
    while ((r = a % b)) {
        a = b;
        b = r;
    }
    return b;
}

ll ll_gcd(ll a, ll b) {
    if (a < b) return ll_gcd(b, a);
    ll r;
    while ((r = a % b)) {
        a = b;
        b = r;
    }
    return b;
}

class UnionFind {
public:
    vector <ll> par;
    vector <ll> siz;
    UnionFind(ll sz_) : par(sz_), siz(sz_, 1LL) {
        for (ll i = 0; i < sz_; ++i) par[i] = i;
    }
    void init(ll sz_) {
        par.resize(sz_);
        siz.assign(sz_, 1LL);
        for (ll i = 0; i < sz_; ++i) par[i] = i;
    }
    ll root(ll x) {
        while (par[x] != x) {
            x = par[x] = par[par[x]];
        }
        return x;
    }
    bool merge(ll x, ll y) {
        x = root(x);
        y = root(y);
        if (x == y) return false;
        if (siz[x] < siz[y]) swap(x, y);
        siz[x] += siz[y];
        par[y] = x;
        return true;
    }

    bool issame(ll x, ll y) {
        return root(x) == root(y);
    }

    ll size(ll x) {
        return siz[root(x)];
    }
};

long long modpow(long long a, long long n, long long mod) {
    long long res = 1;
    while (n > 0) {
        if (n & 1) res = res * a % mod;
        a = a * a % mod;
        n >>= 1;
    }
    return res;
}

long long modinv(long long a, long long mod) {
    return modpow(a, mod - 2, mod);
}

int main() {
    ll n;
    cin >> n;
    ll m;
    cin >> m;
    ll l;
    cin >> l;
    vector<vector<ll>> dp(n,vector<ll>(n,12345678912345));
    for (int i = 0; i < n; i++) {
        dp[i][i] = 0;
    }
    for (int i = 0; i < m; i++) {
        ll a, b, c;
        cin >> a >> b >> c;
        a--;
        b--;
        dp[a][b] = c;
        dp[b][a] = c;
    }
    for (int k = 0; k < n; k++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                dp[i][j] = min(dp[i][j], dp[i][k] + dp[k][j]);
            }
        }
    }
    vector<vector<ll>> dpt(n, vector<ll>(n, 12345678912345));

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (dp[i][j] <= l)dpt[i][j] = 1;
        }
    }
    for (int i = 0; i < n; i++) {
        dpt[i][i] = 0;
    }
    for (int k = 0; k < n; k++) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                dpt[i][j] = min(dpt[i][j], dpt[i][k] + dpt[k][j]);
            }
        }
    }
    ll q;
    cin >> q;
    for (int i = 0; i < q; i++) {
        ll x, y;
        cin >> x >> y;
        x--;
        y--;
        if (dpt[x][y] > 1234567)cout << -1 << endl;
        else cout << dpt[x][y]-1 << endl;
    }
}

Measured memory_bytes: 5056