#region using
using System;
using System.Collections.Generic;
using System.Linq;
using IEnumerable = System.Collections.IEnumerable;
using IEnumerator = System.Collections.IEnumerator;
using BitArray = System.Collections.BitArray;
using BigInteger = System.Numerics.BigInteger;
using TextReader = System.IO.TextReader;
using System.Text;
#endregion

namespace AtCoderProject
{
    public class Program
    {
        public object Calc()
        {
            var N = consoleReader.Int;
            var M = consoleReader.Int;
            L = consoleReader.Int;

            {
                var gb = new LengthGraphBuilder(N);
                for (int i = 0; i < M; i++)
                {
                    var a = consoleReader.Int - 1;
                    var b = consoleReader.Int - 1;
                    var c = consoleReader.Int;
                    if (c <= L)
                        gb.Add(a, b, c);
                }
                graph = gb.ToArray();
            }
            var lengthes = LengthGraphBuilder.WarshallFloyd(graph);
            {
                var gb = new LengthGraphBuilder(N);
                for (int from = 0; from < N; from++)
                    for (int to = from + 1; to < N; to++)
                        if (lengthes[from, to] <= L)
                            gb.Add(from, to, 1);
                countGraph = gb.ToArray();
            }
            var counts = LengthGraphBuilder.WarshallFloyd(countGraph);


            var Q = consoleReader.Int;
            return AllLines(consoleReader.Repeat(Q).Select(cr => counts[cr.Int - 1, cr.Int - 1] - 1).Select(i => i > N ? -1 : i));
        }

        int L;
        Next[][] graph;
        Next[][] countGraph;

        struct Next
        {
            public int to;
            public int length;
            public override string ToString() => $"to: {to} length:{length}";
        }
        class LengthGraphBuilder
        {
            public List<Next>[] lists;
            public LengthGraphBuilder(int count)
            {
                this.lists = new List<Next>[count];
                for (int i = 0; i < count; i++)
                    this.lists[i] = new List<Next>();
            }
            public LengthGraphBuilder(int count, ConsoleReader cr, int edgeCount) : this(count)
            {
                for (int i = 0; i < edgeCount; i++)
                    this.Add(cr.Int - 1, cr.Int - 1, cr.Int);
            }
            public void Add(int from, int to, int length)
            {
                this.lists[from].Add(new Next { to = to, length = length });
                this.lists[to].Add(new Next { to = from, length = length }); // 有向の場合は消す
            }
            public Next[][] ToArray()
            {
                var N = this.lists.Length;
                var res = new Next[N][];
                for (int i = 0; i < N; i++)
                    res[i] = this.lists[i].ToArray();
                return res;
            }
            public static long[,] WarshallFloyd(Next[][] graph)
            {
                var res = new long[graph.Length, graph.Length];
                for (int i = 0; i < graph.Length; i++)
                {
                    for (int j = 0; j < graph.Length; j++)
                    {
                        res[i, j] = long.MaxValue / 2;
                    }
                    res[i, i] = 0;
                    foreach (var next in graph[i])
                        res[i, next.to] = next.length;
                }
                for (int k = 0; k < graph.Length; k++)
                    for (int i = 0; i < graph.Length; i++)
                        for (int j = 0; j < graph.Length; j++)
                            if (res[i, j] > res[i, k] + res[k, j])
                                res[i, j] = res[i, k] + res[k, j];
                return res;
            }
            public static long[] Dijkstra(Next[][] graph, int start)
            {
                var res = new long[graph.Length];
                for (int i = 0; i < res.Length; i++)
                    res[i] = int.MaxValue;
                res[start] = 0;
                var remains = new HashSet<int>(Enumerable.Range(0, graph.Length));
                while (remains.Count > 0)
                {
                    int minIndex = -1;
                    long min = long.MaxValue / 2;
                    foreach (var r in remains)
                    {
                        if (min > res[r])
                        {
                            minIndex = r;
                            min = res[r];
                        }
                    }
                    remains.Remove(minIndex);
                    foreach (var next in graph[minIndex])
                    {
                        var nextLength = min + next.length;
                        if (res[next.to] > nextLength)
                            res[next.to] = nextLength;
                    }
                }
                return res;
            }
        }


        #region いつもの
#pragma warning disable
        [System.Diagnostics.DebuggerBrowsable(System.Diagnostics.DebuggerBrowsableState.Never)] private ConsoleReader consoleReader;
        public Program(ConsoleReader consoleReader) { this.consoleReader = consoleReader; }
        static void Main() => Console.WriteLine(new Program(new ConsoleReader(Console.In)).Calc()); static string AllLines<T>(IEnumerable<T> source) => string.Join("\n", source);
    }
    static class Ext
    {
        public static Dictionary<TKey, int> GroupCount<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector) => source.GroupBy(keySelector).ToDictionary(g => g.Key, g => g.Count());
        public static Dictionary<TKey, int> GroupCount<TKey>(this IEnumerable<TKey> source) => source.GroupCount(i => i);
    }
    public class ConsoleReader { private string[] ReadLineSplit() => textReader.ReadLine().Split(Array.Empty<char>(), StringSplitOptions.RemoveEmptyEntries); private string[] line = Array.Empty<string>(); private int linePosition; private TextReader textReader; public ConsoleReader(TextReader tr) { textReader = tr; } public int Int => int.Parse(String); public long Long => long.Parse(String); public double Double => double.Parse(String); public string String { get { if (linePosition >= line.Length) { linePosition = 0; line = ReadLineSplit(); } return line[linePosition++]; } } public class SplitLine { private string[] splited; public SplitLine(ConsoleReader cr) { splited = cr.ReadLineSplit(); cr.line = Array.Empty<string>(); } public int[] Int => String.Select(x => int.Parse(x)).ToArray(); public int[] Int0 => String.Select(x => int.Parse(x) - 1).ToArray(); public long[] Long => String.Select(x => long.Parse(x)).ToArray(); public double[] Double => String.Select(x => double.Parse(x)).ToArray(); public string[] String => splited; } public SplitLine Split => new SplitLine(this); public class RepeatReader : IEnumerable<ConsoleReader> { ConsoleReader cr; int count; public RepeatReader(ConsoleReader cr, int count) { this.cr = cr; this.count = count; } public IEnumerator<ConsoleReader> GetEnumerator() => Enumerable.Repeat(cr, count).GetEnumerator(); System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() => GetEnumerator(); public IEnumerable<string> String => this.Select(cr => cr.String); public IEnumerable<int> Int => this.Select(cr => cr.Int); public IEnumerable<int> Int0 => this.Select(cr => cr.Int - 1); public IEnumerable<long> Long => this.Select(cr => cr.Long); public IEnumerable<double> Double => this.Select(cr => cr.Double); } public RepeatReader Repeat(int count) => new RepeatReader(this, count); }
    #endregion
}


Measured memory_bytes: 21564