#include "bits/stdc++.h"

using namespace std;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;
typedef long long LL;
typedef priority_queue<int> PQ_DESC;
typedef priority_queue<int, vector<int>, greater<int>> PQ_ASC;
typedef priority_queue<PII> PQ_DESC_PII;
typedef priority_queue<PII, vector<PII>, greater<PII>> PQ_ASC_PII;
 
#define SORT_ASC(c) sort((c).begin(), (c).end())
#define SORT_DESC(c) sort((c).begin(), (c).end(), greater<typeof((c).begin())>())
 
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define SIZE(a) int((a).size())
 
const double EPS = 1e-10;
const double PI  = acos(-1.0);
const int INT_LARGE = 1000000100;


//debug func
template<typename T>
void vecprint(vector<T> v) {
    for(auto x : v) {
        cout << x << " ";
    }
    cout << endl;
}

template<typename T>
void vecvecprint(vector<vector<T>> v) {
    for(auto x :v) {
        REP(i, x.size()-1) {
            cerr << x[i] << " ";
        }
        cerr << x[x.size()-1] <<endl;
    }
}

template<typename T>
void pqprint(priority_queue<T> q) {
    while(!q.empty()) {
        cout << q.top() << " ";
        q.pop();
    }
    cout << endl;
}

template<typename T>
void qprint(queue<T> q) {
    while(!q.empty()) {
        cout << q.front() << " ";
        q.pop();
    }
    cout << endl;
}

template<typename T>
void vecqprint(vector<queue<T>> v) {
    for(int i = 0; i < v.size(); i++) {
        qprint(v[i]);
    }
}

template <typename Iterator>
inline bool next_combination(const Iterator first, Iterator k, const Iterator last)
{
   /* Credits: Thomas Draper */
   if ((first == last) || (first == k) || (last == k))
      return false;
   Iterator itr1 = first;
   Iterator itr2 = last;
   ++itr1;
   if (last == itr1)
      return false;
   itr1 = last;
   --itr1;
   itr1 = k;
   --itr2;
   while (first != itr1)
   {
      if (*--itr1 < *itr2)
      {
         Iterator j = k;
         while (!(*itr1 < *j)) ++j;
         iter_swap(itr1,j);
         ++itr1;
         ++j;
         itr2 = k;
         rotate(itr1,j,last);
         while (last != j)
         {
            ++j;
            ++itr2;
         }
         rotate(k,itr2,last);
         return true;
      }
   }
   rotate(first,k,last);
   return false;
}



int main(void) {
    int n, m, l;
    cin >> n >> m >> l;
    
    vector<vector<LL>> vvd(n, vector<LL>(n, (LL)INT_MAX));
    
    REP(i, m) {
        int a, b, c;
        cin >> a >> b >> c;
        vvd[a-1][b-1] = c;
        vvd[b-1][a-1] = c;
    }
    
    vecvecprint(vvd);
    
    REP(i, n) {
        REP(j, n) {
            REP(k, n) {
                if(vvd[j][k] > vvd[j][i] + vvd[i][k]) vvd[j][k] = vvd[j][i] + vvd[i][k];
            }
        }
    }
    vecvecprint(vvd);
    
    vector<vector<LL>> vvg(n, vector<LL>(n, (LL)INT_MAX));
    REP(i, n) {
        REP(j, n) {
            if(vvd[i][j] <= l) vvg[i][j] = 1;
        }
    }
    vecvecprint(vvg);
    
    REP(i, n) {
        REP(j, n) {
            REP(k, n) {
                if(vvg[j][k] > vvg[j][i] + vvg[i][k]) vvg[j][k] = vvg[j][i] + vvg[i][k];
            }
        }
    }
    vecvecprint(vvg);
    
    int q;
    cin >> q;
    REP(i, q) {
        int s, t;
        cin >> s >> t;
        if(vvg[s-1][t-1] < INT_MAX)cout << vvg[s-1][t-1]-1 << endl;
        else cout << -1 << endl;
    }
}


Measured memory_bytes: 2424