#include <bits/stdc++.h>

#define PI acos(-1)
#define all(a) a.begin(), a.end()
#define full(a, n) a, a + n
#define ma(type, size) (type *)malloc(sizeof(type) * size)
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define MT make_tuple
#define f0(i, n) for (i = 0; i < (n); i++)
#define f1(i, n) for (i = 1; i < (n); i++)
#define f1n(i, n) for (i = 1; i <= (n); i++)
#define fab(i, a, b) for (i = (a); i <= (b); i++)
#define fr(i, b, a) for (i = (b); i >= (a); i--)

using namespace std;

/*
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,
	tree_order_statistics_node_update> indexed_set;
//*/
typedef long long int ll;
typedef long int lo;

typedef vector<ll> vll;
typedef pair<ll, ll> pll;
typedef tuple<ll, ll, ll> tll;

//* utility function
inline bool compare(ll i, ll j)
{
    return i < j;
}
//*/

//* function prototypes
template< typename T>
T gcd(T a, T b);
template< typename T>
T modpow(T number, T power, T mod_value);
//*/

//int row, column;
//int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
//int dy[8] = {0, -1, -1, -1, 0, 1, 1, 1};
//int dx[4] = {1,  0, -1, 0};
//int dy[4] = {0, -1,  0, 1};
//ll p2[63] = {1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, 67108864, 134217728, 268435456, 536870912, 1073741824, 2147483648, 4294967296, 8589934592, 17179869184, 34359738368, 68719476736, 137438953472, 274877906944, 549755813888, 1099511627776, 2199023255552, 4398046511104, 8796093022208, 17592186044416, 35184372088832, 70368744177664, 140737488355328, 281474976710656, 562949953421312, 1125899906842624, 2251799813685248, 4503599627370496, 9007199254740992, 18014398509481984, 36028797018963968, 72057594037927936, 144115188075855872, 288230376151711744, 576460752303423488, 1152921504606846976, 2305843009213693952, 4611686018427387904};
#ifdef DEBUG
#endif // DEBUG
//#define DEBUG
#define INF 1e12
struct data
{
    ll fuel;
    ll fillup;
    data(ll fuel = 0, ll fillup = 0):fuel(fuel), fillup(fillup) {}
};
typedef data DATA;

int main()
{
    //ios::sync_with_stdio(0);
    //cin.tie(0);
    //cout.tie(0);
    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);

    ll number_of_test_case = 1, test_case;
    //cin >> number_of_test_case;
    for (test_case = 1; test_case <= number_of_test_case; test_case++)
    {
        ll n, m, l, i;

        cin >> n >> m >> l;
        vector<pll> adj[n+1];

        ll a, b, c;
        f0(i, m)
        {
            cin >> a >> b >> c;
            if (c > l)
                continue;

            adj[a].PB(MP(b, c));
            adj[b].PB(MP(a, c));
        }

        pll distance[n+1][n+1];// first = fill , second = remaining fuel

        f1n(i, n)
        {
            for (ll j = 1; j <= n; j++)
                distance[i][j] = MP(INF, 0);

            ll fuel, fillup, node;

            distance[i][i] = {0ll, l};
            bool processed[n+1] = {};

            priority_queue<tll>q;// 0=fill , 1=fuel, 2=node
            q.push(MT(0ll, l, i));
            while (!q.empty())
            {
                //int a = q.top().second;
                tie(fillup, fuel, node) = q.top();
                q.pop();
                fillup *= -1;
#ifdef DEBUG
                cout << "now processing node " << node << endl
                    << "remaining fuel " << fuel << "\n"
                    << "refill " << fillup << "\n\n";
#endif // DEBUG


                if (processed[node])
                    continue;
                processed[node] = true;

                for (auto u : adj[node])
                {
                    ll b = u.first, w = u.second;
                    ll temp_fill = fillup;
                    ll temp_fuel = fuel;
                    if (fuel < w)
                    {
                        temp_fill++;
                        temp_fuel = l;
                    }
                    temp_fuel -= w;

                    if (temp_fill < distance[i][b].first || (temp_fill == distance[i][b].first && temp_fuel > distance[i][b].S))
                    {
                        distance[i][b] = MP(temp_fill, temp_fuel);
                        q.push(MT(-temp_fill, temp_fuel, b));
                    }
                }
            }
        }

        ll q;
        cin >> q;

        f0(i, q)
        {
            cin >> a >> b;

            cout << (distance[a][b].first == INF ? -1 : distance[a][b].first) << endl;

        }


        //cout << "Test #" << test_case << ": ";
        //cout << "Case " << test_case << ": ";
    }
    return 0;
}


template< typename T>
T gcd(T a, T b)
{
    if (b == 0)
        return a;
    return gcd(b, a%b);
}
template< typename T>
T modpow(T number, T power, T mod_value)
{
    if (power == 0)
        return 1%mod_value;
    ll u = modpow(number,power/2,mod_value);
    u = (u*u)%mod_value;
    if (power%2 == 1)
        u = (u*number)%mod_value;
    return u;
}


Measured memory_bytes: 5652