/*                                                                                
                      Keyblinds Guide
     				###################
      @Ntsc 2024

      - Ctrl+Alt+G then P : Enter luogu problem details
      - Ctrl+Alt+B : Run all cases in CPH
      - ctrl+D : choose this and dump to the next
      - ctrl+Shift+L : choose all like this
      - ctrl+K then ctrl+W: close all
      - Alt+la/ra : move mouse to pre/nxt pos'
	  
*/
#include <bits/stdc++.h>
#include <queue>
using namespace std;

#define rep(i, l, r) for (int i = l, END##i = r; i <= END##i; ++i)
#define per(i, r, l) for (int i = r, END##i = l; i >= END##i; --i)
#define pb push_back
#define mp make_pair
#define int long long
#define ull unsigned long long
#define pii pair<int, int>
#define ps second
#define pf first

// #define innt int
#define itn int
// #define inr intw
// #define mian main
// #define iont int

#define rd read()
int read(){
    int xx = 0, ff = 1;
    char ch = getchar();
    while (ch < '0' || ch > '9') {
		if (ch == '-')
			ff = -1;
		ch = getchar();
    }
    while (ch >= '0' && ch <= '9')
      xx = xx * 10 + (ch - '0'), ch = getchar();
    return xx * ff;
}
void write(int out) {
	if (out < 0)
		putchar('-'), out = -out;
	if (out > 9)
		write(out / 10);
	putchar(out % 10 + '0');
}



#define zerol = 1
#ifdef zerol
#define cdbg(x...) do { cerr << #x << " -> "; err(x); } while (0)
void err() { cerr << endl; }
template<template<typename...> class T, typename t, typename... A>
void err(T<t> a, A... x) { for (auto v: a) cerr << v << ' '; err(x...); }
template<typename T, typename... A>
void err(T a, A... x) { cerr << a << ' '; err(x...); }
#else
#define dbg(...)
#endif


const int N = 3e2 + 5;
const int INF = 1e18;
const int M = 1e7;
const int MOD = 1e9 + 7;


int d[N][N];
int f[N][N];



void solve(){
    int n=rd,m=rd,L=rd;
    
    memset(d,0x3f3f,sizeof d);
    // cdbg(d[1][1].pf,d[1][1].ps);

    for(int i=1;i<=m;i++){
        int a=rd,b=rd,c=rd;
        if(c>L)continue;
        d[a][b]=d[b][a]=min(d[a][b],c);
    }

    for(int i=1;i<=n;i++){
        d[i][i]=0;
    }

    // cdbg(min(mp(2,1),mp(2,2))==mp(2,2));

    for(int k=1;k<=n;k++){
        for(int i=1;i<=n;i++){
            for(int j=1;j<=n;j++){
                d[i][j]=min(d[i][j],d[i][k]+d[k][j]);
            }
        }
    }

    // cdbg(d[2][4].pf,d[2][4].ps);
    // cdbg(d[4][5].pf,d[4][5].ps);

    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(i==j)continue;
            if(d[i][j]<=L)f[i][j]=1;
            else f[i][j]=INF;
        }
    }
    
    for(int k=1;k<=n;k++){
        for(int i=1;i<=n;i++){
            for(int j=1;j<=n;j++){
                f[i][j]=min(f[i][j],f[i][k]+f[k][j]);
            }
        }
    }


    int q=rd;
    while(q--){
        int a=rd,b=rd;
        int ans=f[a][b];
        if(ans>=INF)ans=0;
        cout<<ans-1<<endl;
    }
}

signed main() {
    // freopen(".in","r",stdin);
    // freopen(".in","w",stdout);

    int T=1;
    while(T--){
    	solve();
    }
    return 0;
}