#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pullull;
typedef pair<ll, int> plli;
typedef pair<int, pii> pipii;
typedef vector<vector<int> > mati;
typedef vector<vector<double> > matd;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef vector<pll> vpll;
typedef vector<vector<pll>> vvpll;

#define FOR(i,x,y) for(ll i=(ll)x; i<(ll)y; ++i)
#define REP(i,y) FOR(i, 0, y)
#define RFOR(i,x,y) for(ll i=(ll)x; i>=(ll)y; --i)
#define RREP(i,x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back

inline void IN(void){
  return;
}

template <typename First, typename... Rest>
void IN(First& first, Rest&... rest){
  cin >> first;
  IN(rest...);
  return;
}

inline void OUT(void){
  cout << "\n";
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest){
  cout << first << " ";
  OUT(rest...);
  return;
}

template <typename T>
void vec_print(vector<T> VEC){
  REP(i, VEC.size()){
    cout << VEC[i] << " ";
  }
  cout << "\n";
};

template <typename T>
void mat_print(vector<vector<T> > MAT){
  REP(i, MAT.size()){
    REP(j, MAT[i].size()){
      cout << MAT[i][j] << " ";
    }
    cout << "\n";
  }
};

template <typename CLASS1, typename CLASS2>
class HOGE{
  public:
    CLASS1 key;
    CLASS2 value;
    HOGE(void){
      return;
    };
    HOGE(CLASS1 key, CLASS2 value){
      this->key = key;
      this->value = value;
    };
    ~HOGE(void){
      return;
    };

    void print(void){
      cout << "key : " << key << ", value : " << value << "\n";
      return;
    };
    
    bool operator==(const HOGE &obj){
      return (this->value == obj.value);
    };
    bool operator<(const HOGE &obj){
      return (this->value < obj.value);
    };
    bool operator>(const HOGE &obj){
      return (this->value > obj.value);
    };
};

template <typename CLASS1, typename CLASS2>
bool operator==(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value == hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator<(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value < hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator>(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value > hoge2.value;
};

constexpr int INF = (1<<30);
constexpr ll INFLL = 1LL<<62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)((1E+9)+7);

class Warshall_Floyd{
  //Warshall-Floyd algorithm
  //calculation time complexity: O(|V|^3)
  //all vertex-vertex minimum distance
  private:
    ll V;
    vector<vector<ll> > d;

  public:
    Warshall_Floyd(ll V, vector<ll> From, vector<ll> To, vector<ll> Cost){
      //num of vertex
      this->V = V;
      d.resize(V);
      for(ll i=0; i<V; ++i){
        d[i].resize(V, INFLL-1);
        d[i][i] = 0;
      }
      ll E = (ll)From.size();
      if((ll)To.size() != E || (ll)Cost.size() != E){
        fprintf(stderr, "Sizes are different, %ld %ld %ld\n", From.size(), To.size(), Cost.size());
        exit(0);
      }

      for(ll i=0; i<E; ++i){
        d[From[i]][To[i]] = Cost[i];
      }
      return;
    };

    ~Warshall_Floyd(void){
      return;
    };

    void shortest_path(void){
      for(ll k=0; k<V; ++k){
        for(ll i=0; i<V; ++i){
          for(ll j=0; j<V; ++j){
            //d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
            if(d[i][j] > d[i][k] + d[k][j]){
              d[i][j] = d[i][k] + d[k][j];
            }
          }
        }
      }
      return;
    };

    ll get_distance(ll s, ll e){
      return d[s][e];
    };
};

ll N, M, L;
vll A, B, C;
vvpll Connect_Path;
vvll Path;

int main(){
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after std::cin)
  ios::sync_with_stdio(false); // cut the iostream and stdio (DON'T endl; BUT "\n";)

  vll From0, To0, Cost0;

  IN(N,M,L);
  A.resize(M);
  B.resize(M);
  C.resize(M);
  Connect_Path.resize(N);
  Path.resize(N);
  REP(i,M){
    IN(A[i], B[i], C[i]);
    A[i]--;
    B[i]--;
    From0.pb(A[i]);
    To0.pb(B[i]);
    Cost0.pb(C[i]);
    From0.pb(B[i]);
    To0.pb(A[i]);
    Cost0.pb(C[i]);
  }

  Warshall_Floyd WF0(N, From0, To0, Cost0);
  WF0.shortest_path();

  vll From, To, Cost;
  REP(i,N){
    REP(j,N){
      if(WF0.get_distance(i, j) <= L){
        From.pb(i);
        To.pb(j);
        Cost.pb(1);
      }
    }
  }

  //mat_print(Path);

  Warshall_Floyd WF(N, From, To, Cost);
  WF.shortest_path();

  ll Q;
  IN(Q);
  vll s(Q), t(Q);
  REP(i,Q){
    IN(s[i], t[i]);
    s[i]--;
    t[i]--;
    ll ans = WF.get_distance(s[i], t[i]);
    if(ans>N) ans = 0;
    OUT(ans-1);
  }

  return 0;
}

Measured memory_bytes: 9644