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

#define endl '\n'
#define ALL(a)  (a).begin(),(a).end()
#define ALLR(a)  (a).rbegin(),(a).rend()
#define spa << " " <<
#define test cout<<"test"<<endl;
#define fi first
#define se second
#define MP make_pair
#define PB push_back
#define EB emplace_back
#define rep(i,n,m) for(ll i = n; i < (ll)(m); i++)
#define rrep(i,n,m) for(ll i = m - 1; i >= (ll)(n); i--)
using ll = long long;
using ld = long double;
const ll MOD = 1e9+7;
//const ll MOD = 998244353;
const ll INF = 1e18;
template<typename T>
void chmin(T &a,T b){if(a>b)a=b;}
template<typename T>
void chmax(T &a,T b){if(a<b)a=b;}
void pmod(ll &a,ll b){a=(a+b)%MOD;}
void pmod(ll &a,ll b,ll c){a=(b+c)%MOD;}
void qmod(ll &a,ll b){a=(a*b)%MOD;}
void qmod(ll &a,ll b,ll c){a=(b*c)%MOD;}
ll median(ll a,ll b, ll c){return a+b+c-max({a,b,c})-min({a,b,c});}
void ans1(bool x){if(x) cout<<"Yes"<<endl;else cout<<"No"<<endl;}
void ans2(bool x){if(x) cout<<"YES"<<endl;else cout<<"NO"<<endl;}
void ans3(bool x){if(x) cout<<"Yay!"<<endl;else cout<<":("<<endl;}
template<typename T1,typename T2>
void ans(bool x,T1 y,T2 z){if(x)cout<<y<<endl;else cout<<z<<endl;}  
template<typename T>
void debug(vector<vector<T>>&v,ll h,ll w){for(ll i=0;i<h;i++)
{cout<<v[i][0];for(ll j=1;j<w;j++)cout spa v[i][j];cout<<endl;}};
void debug(vector<string>&v,ll h,ll w){for(ll i=0;i<h;i++)
{for(ll j=0;j<w;j++)cout<<v[i][j];cout<<endl;}};
template<typename T>
void debug(vector<T>&v,ll n){if(n!=0)cout<<v[0];
for(ll i=1;i<n;i++)cout spa v[i];cout<<endl;};
template<typename T>
vector<vector<T>>vec(ll x, ll y, T w){
  vector<vector<T>>v(x,vector<T>(y,w));return v;}
ll gcd(ll x,ll y){ll r;while(y!=0&&(r=x%y)!=0){x=y;y=r;}return y==0?x:y;}
vector<ll>dx={1,0,-1,0,1,1,-1,-1};
vector<ll>dy={0,1,0,-1,1,-1,1,-1};
template<typename T>
vector<T> make_v(size_t a,T b){return vector<T>(a,b);}
template<typename... Ts>
auto make_v(size_t a,Ts... ts){
  return vector<decltype(make_v(ts...))>(a,make_v(ts...));
}

ll MAX_V = 500;
struct edge {
  ll to,cost;
  edge(ll x,ll y):to(x),cost(y){};
};
//<最短距離, 頂点の番号>
using P = pair<pair<ll,ll>,ll>;
vector<vector<struct edge>> G(MAX_V); //隣接リスト
vector<pair<ll,ll>> d(MAX_V); //各頂点への最短距離
void dijkstra(ll s,ll l) {
    priority_queue<P, vector<P>, greater<P> > que;
    fill(ALL(d), MP(INF,INF));
    d[s] = MP(0,-l);
    que.emplace(MP(0, -l),s);
    while (!que.empty()) {
        auto p = que.top();
        que.pop();
        ll v = p.se;
        if (d[v] < p.fi) continue;
        //if(d[v].fi==p.fi.fi&&d[v].se<p.fi.se)continue;
        for (ll i=0; i<G[v].size(); i++) {
            struct edge e = G[v][i];
            auto tmp=p;
            if(p.fi.se+e.cost>0){
              p.fi.se=-l+e.cost;
              p.fi.fi++;
            }
            else p.fi.se+=e.cost;
            if (d[e.to] > p.fi) {
              //if(s==0)cout<<p.fi.fi spa p.fi.se spa p.se<<endl;
              d[e.to] = p.fi;
              que.emplace(d[e.to], e.to);
            }
            p=tmp;
        }
    }
}
int main(){
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  //cout<<fixed<<setprecision(10);
  ll res=0,buf=0;
  bool judge = true;
  ll n,m,l;cin>>n>>m>>l;
  for(ll i=0;i<m;i++){
    ll u,v,c;
    cin>>u>>v>>c;
    u--;v--;
    if(c<=l){
      struct edge e ={v,c};
      G[u].push_back(e);
      e ={u,c};
      G[v].push_back(e);
    }
  }
  auto mat=vec(n,n,INF);
  rep(i,0,n){
    dijkstra(i,l);
    rep(j,0,n)mat[i][j]=d[j].fi;
    if(i>=0){
      //rep(j,0,n)cout<<i spa d[j].fi spa d[j].se<<endl;
    }
  }
  ll q;cin>>q;
  while(q--){
    ll s,t;cin>>s>>t;
    if(mat[s-1][t-1]==INF)cout<<-1<<endl;
    else cout<<mat[s-1][t-1]<<endl;
  }
  return 0;
}


Measured memory_bytes: 4936