package main

import (
	"bufio"
	"container/heap"
	"errors"
	"fmt"
	"io"
	"math"
	"os"
	"strconv"
)

/*********** I/O ***********/

var (
	// ReadString returns a WORD string.
	ReadString func() string
	stdout     *bufio.Writer
)

func init() {
	ReadString = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func newReadString(ior io.Reader) func() string {
	r := bufio.NewScanner(ior)
	// r.Buffer(make([]byte, 1024), int(1e+11)) // for AtCoder
	r.Buffer(make([]byte, 1024), int(1e+9)) // for Codeforces
	// Split sets the split function for the Scanner. The default split function is ScanLines.
	// Split panics if it is called after scanning has started.
	r.Split(bufio.ScanWords)

	return func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
}

// ReadInt returns an integer.
func ReadInt() int {
	return int(readInt64())
}
func ReadInt2() (int, int) {
	return int(readInt64()), int(readInt64())
}
func ReadInt3() (int, int, int) {
	return int(readInt64()), int(readInt64()), int(readInt64())
}
func ReadInt4() (int, int, int, int) {
	return int(readInt64()), int(readInt64()), int(readInt64()), int(readInt64())
}

// ReadInt64 returns as integer as int64.
func ReadInt64() int64 {
	return readInt64()
}
func ReadInt64_2() (int64, int64) {
	return readInt64(), readInt64()
}
func ReadInt64_3() (int64, int64, int64) {
	return readInt64(), readInt64(), readInt64()
}
func ReadInt64_4() (int64, int64, int64, int64) {
	return readInt64(), readInt64(), readInt64(), readInt64()
}

func readInt64() int64 {
	i, err := strconv.ParseInt(ReadString(), 0, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

// ReadIntSlice returns an integer slice that has n integers.
func ReadIntSlice(n int) []int {
	b := make([]int, n)
	for i := 0; i < n; i++ {
		b[i] = ReadInt()
	}
	return b
}

// ReadInt64Slice returns as int64 slice that has n integers.
func ReadInt64Slice(n int) []int64 {
	b := make([]int64, n)
	for i := 0; i < n; i++ {
		b[i] = ReadInt64()
	}
	return b
}

// ReadFloat64 returns an float64.
func ReadFloat64() float64 {
	return float64(readFloat64())
}

func readFloat64() float64 {
	f, err := strconv.ParseFloat(ReadString(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

// ReadFloatSlice returns an float64 slice that has n float64.
func ReadFloat64Slice(n int) []float64 {
	b := make([]float64, n)
	for i := 0; i < n; i++ {
		b[i] = ReadFloat64()
	}
	return b
}

// ReadRuneSlice returns a rune slice.
func ReadRuneSlice() []rune {
	return []rune(ReadString())
}

/*********** Debugging ***********/

// ZeroPaddingRuneSlice returns binary expressions of integer n with zero padding.
// For debugging use.
func ZeroPaddingRuneSlice(n, digitsNum int) []rune {
	sn := fmt.Sprintf("%b", n)

	residualLength := digitsNum - len(sn)
	if residualLength <= 0 {
		return []rune(sn)
	}

	zeros := make([]rune, residualLength)
	for i := 0; i < len(zeros); i++ {
		zeros[i] = '0'
	}

	res := []rune{}
	res = append(res, zeros...)
	res = append(res, []rune(sn)...)

	return res
}

/*********** DP sub-functions ***********/

// ChMin accepts a pointer of integer and a target value.
// If target value is SMALLER than the first argument,
//	then the first argument will be updated by the second argument.
func ChMin(updatedValue *int, target int) bool {
	if *updatedValue > target {
		*updatedValue = target
		return true
	}
	return false
}

// ChMax accepts a pointer of integer and a target value.
// If target value is LARGER than the first argument,
//	then the first argument will be updated by the second argument.
func ChMax(updatedValue *int, target int) bool {
	if *updatedValue < target {
		*updatedValue = target
		return true
	}
	return false
}

// NthBit returns nth bit value of an argument.
// n starts from 0.
func NthBit(num, nth int) int {
	return num >> uint(nth) & 1
}

// OnBit returns the integer that has nth ON bit.
// If an argument has nth ON bit, OnBit returns the argument.
func OnBit(num, nth int) int {
	return num | (1 << uint(nth))
}

// OffBit returns the integer that has nth OFF bit.
// If an argument has nth OFF bit, OffBit returns the argument.
func OffBit(num, nth int) int {
	return num & ^(1 << uint(nth))
}

// PopCount returns the number of ON bit of an argument.
func PopCount(num int) int {
	res := 0

	for i := 0; i < 70; i++ {
		if ((num >> uint(i)) & 1) == 1 {
			res++
		}
	}

	return res
}

/*********** Arithmetic ***********/

// Max returns the max integer among input set.
// This function needs at least 1 argument (no argument causes panic).
func Max(integers ...int) int {
	m := integers[0]
	for i, integer := range integers {
		if i == 0 {
			continue
		}
		if m < integer {
			m = integer
		}
	}
	return m
}

// Min returns the min integer among input set.
// This function needs at least 1 argument (no argument causes panic).
func Min(integers ...int) int {
	m := integers[0]
	for i, integer := range integers {
		if i == 0 {
			continue
		}
		if m > integer {
			m = integer
		}
	}
	return m
}

// Sum returns multiple integers sum.
func Sum(integers ...int) int {
	s := 0

	for _, i := range integers {
		s += i
	}

	return s
}

// PowInt is integer version of math.Pow
// PowInt calculate a power by Binary Power (二分累乗法(O(log e))).
func PowInt(a, e int) int {
	if a < 0 || e < 0 {
		panic(errors.New("[argument error]: PowInt does not accept negative integers"))
	}

	if e == 0 {
		return 1
	}

	if e%2 == 0 {
		halfE := e / 2
		half := PowInt(a, halfE)
		return half * half
	}

	return a * PowInt(a, e-1)
}

// AbsInt is integer version of math.Abs
func AbsInt(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

// Gcd returns the Greatest Common Divisor of two natural numbers.
// Gcd only accepts two natural numbers (a, b >= 1).
// 0 or negative number causes panic.
// Gcd uses the Euclidean Algorithm.
func Gcd(a, b int) int {
	if a <= 0 || b <= 0 {
		panic(errors.New("[argument error]: Gcd only accepts two NATURAL numbers"))
	}
	if a < b {
		a, b = b, a
	}

	// Euclidean Algorithm
	for b > 0 {
		div := a % b
		a, b = b, div
	}

	return a
}

// Lcm returns the Least Common Multiple of two natural numbers.
// Lcd only accepts two natural numbers (a, b >= 1).
// 0 or negative number causes panic.
// Lcd uses the Euclidean Algorithm indirectly.
func Lcm(a, b int) int {
	if a <= 0 || b <= 0 {
		panic(errors.New("[argument error]: Gcd only accepts two NATURAL numbers"))
	}

	// a = a'*gcd, b = b'*gcd, a*b = a'*b'*gcd^2
	// a' and b' are relatively prime numbers
	// gcd consists of prime numbers, that are included in a and b
	gcd := Gcd(a, b)

	// not (a * b / gcd), because of reducing a probability of overflow
	return (a / gcd) * b
}

// Strtoi is a wrapper of strconv.Atoi().
// If strconv.Atoi() returns an error, Strtoi calls panic.
func Strtoi(s string) int {
	if i, err := strconv.Atoi(s); err != nil {
		panic(errors.New("[argument error]: Strtoi only accepts integer string"))
	} else {
		return i
	}
}

// PrintIntsLine returns integers string delimited by a space.
func PrintIntsLine(A ...int) string {
	res := []rune{}

	for i := 0; i < len(A); i++ {
		str := strconv.Itoa(A[i])
		// str := strconv.FormatInt(A[i], 10)  // 64bit int version
		res = append(res, []rune(str)...)

		if i != len(A)-1 {
			res = append(res, ' ')
		}
	}

	return string(res)
}

/********** FAU standard libraries **********/

//fmt.Sprintf("%b\n", 255) 	// binary expression

/********** I/O usage **********/

//str := ReadString()
//i := ReadInt()
//X := ReadIntSlice(n)
//S := ReadRuneSlice()
//a := ReadFloat64()
//A := ReadFloat64Slice(n)

//str := ZeroPaddingRuneSlice(num, 32)
//str := PrintIntsLine(X...)

/*******************************************************************/

const MOD = 1000000000 + 7
const ALPHABET_NUM = 26
const INF_INT64 = math.MaxInt64
const INF_BIT60 = 1 << 60

var n, m, l int
var A, B, C []int
var q int

var answers [300 + 5][300 + 5]int

func main() {
	n, m, l = ReadInt3()
	v, e = n, m
	A, B, C = make([]int, m), make([]int, m), make([]int, m)
	for i := 0; i < m; i++ {
		a, b, c := ReadInt3()
		a--
		b--
		if l < c {
			continue
		}

		A[i], B[i], C[i] = a, b, c
		G[a] = append(G[a], Edge{to: b, cost: c})
		G[b] = append(G[b], Edge{to: a, cost: c})
	}

	// 前計算
	for i := 0; i < n; i++ {
		Dijkstra(i)
		for j := 0; j < n; j++ {
			if dp[j].times < INF_30 {
				answers[i][j] = dp[j].times
			} else {
				answers[i][j] = -1
			}
		}
	}

	q = ReadInt()
	for i := 0; i < q; i++ {
		s, t := ReadInt2()
		s--
		t--
		fmt.Println(answers[s][t])
	}
}

type Edge struct {
	to   int
	cost int
}

type Vertex struct {
	pri            int
	id, gas, times int
}
type VertexPQ []*Vertex

func (pq VertexPQ) Len() int { return len(pq) }
func (pq VertexPQ) Less(i, j int) bool {
	if pq[i].times < pq[j].times {
		return true
	} else if pq[i].times > pq[j].times {
		return false
	} else {
		if pq[i].gas > pq[j].gas {
			return true
		} else {
			return false
		}
	}
	// return pq[i].pri < pq[j].pri
} // <: ASC, >: DESC
func (pq VertexPQ) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}
func (pq *VertexPQ) Push(x interface{}) {
	item := x.(*Vertex)
	*pq = append(*pq, item)
}
func (pq *VertexPQ) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	*pq = old[0 : n-1]
	return item
}

// how to use
// temp := make(VertexPQ, 0, 100000+1)
// pq := &temp
// heap.Init(pq)
// heap.Push(pq, &Vertex{pri: intValue})
// popped := heap.Pop(pq).(*Vertex)

// 蟻本/AOJ
// 隣接リストで辺を管理
// node idは0-based

const MAX_NODE_NUM = 300 + 5 // 最大ノード数
// const INF_30 = 1 << 30       // dpテーブル初期化用
const INF_30 = 1 << 60 // dpテーブル初期化用

var v, e int                   // v: 頂点数, e: 辺数
var G [MAX_NODE_NUM + 5][]Edge // G: 隣接リストによるグラフ
// var dp [MAX_NODE_NUM + 5]int   // dp: 単一始点からの距離
var dp [MAX_NODE_NUM + 5]Vertex
var flags [MAX_NODE_NUM + 5]bool

// sidを始点としてダイクストラ法を実行
// O(|E| * log|V|)
func Dijkstra(sid int) {
	// 昇順で取り出せるpriority queue
	temp := make(VertexPQ, 0, 200000+5)
	pq := &temp
	heap.Init(pq)

	// 初期化
	for i := 0; i < v; i++ {
		// dp[i] = INF_30
		// dp[i] = Vertex{gas: 0, times: INF_30} // idはいらないはず
		dp[i] = Vertex{gas: -1, times: INF_30} // idはいらないはず
		flags[i] = false
	}
	// dp[sid] = 0
	dp[sid] = Vertex{gas: l, times: 0}
	// heap.Push(pq, &Node{pri: dp[sid], dist: dp[sid], id: sid})
	heap.Push(pq, &Vertex{gas: dp[sid].gas, times: dp[sid].times, id: sid})

	for pq.Len() > 0 {
		// node := heap.Pop(pq).(*Node)
		vertex := heap.Pop(pq).(*Vertex)
		// v := node.id
		v := vertex.id

		// 最短距離でなければ無視する
		// if dp[v] < node.dist {
		// 	continue
		// }
		if flags[v] {
			continue
		}
		flags[v] = true

		// if dp[v].times < vertex.times {
		// 	continue
		// } else if dp[v].times == vertex.times && dp[v].gas > vertex.gas {
		// 	continue
		// }

		for _, e := range G[v] {
			// if dp[e.to] > dp[v]+e.cost {
			// 	dp[e.to] = dp[v] + e.cost
			// 	heap.Push(pq, &Node{pri: dp[e.to], dist: dp[e.to], id: e.to})
			// }

			// 補給無しでいけるかどうかチェック
			if dp[v].gas >= e.cost {
				// 補給無し
				if dp[e.to].times > dp[v].times {
					// 回数が小さいなら必ず更新
					dp[e.to].times = dp[v].times
					dp[e.to].gas = dp[v].gas - e.cost
					heap.Push(pq, &Vertex{gas: dp[e.to].gas, times: dp[e.to].times, id: e.to})
				} else if dp[e.to].times == dp[v].times && dp[e.to].gas < dp[v].gas-e.cost {
					// 回数が同じでもガソリンが多いなら更新
					dp[e.to].gas = dp[v].gas - e.cost
					heap.Push(pq, &Vertex{gas: dp[e.to].gas, times: dp[e.to].times, id: e.to})
				}
			} else {
				// 補給あり
				// 補給しても通れないならパス
				if l < e.cost {
					continue
				}

				if dp[e.to].times > dp[v].times+1 {
					// 回数が小さいなら必ず更新
					dp[e.to].times = dp[v].times + 1
					dp[e.to].gas = l - e.cost
					heap.Push(pq, &Vertex{gas: dp[e.to].gas, times: dp[e.to].times, id: e.to})
				} else if dp[e.to].times == dp[v].times+1 && dp[e.to].gas < l-e.cost {
					// 回数が同じでもガソリンが多いなら更新
					dp[e.to].gas = l - e.cost
					heap.Push(pq, &Vertex{gas: dp[e.to].gas, times: dp[e.to].times, id: e.to})
				}
			}
		}
	}
}

// type Edge struct {
// 	to   int
// 	cost int
// }

type Node struct {
	pri      int
	dist, id int
}
type NodePQ []*Node

func (pq NodePQ) Len() int           { return len(pq) }
func (pq NodePQ) Less(i, j int) bool { return pq[i].pri < pq[j].pri } // <: ASC, >: DESC
func (pq NodePQ) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}
func (pq *NodePQ) Push(x interface{}) {
	item := x.(*Node)
	*pq = append(*pq, item)
}
func (pq *NodePQ) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	*pq = old[0 : n-1]
	return item
}

// how to use
// temp := make(NodePQ, 0, 100000+1)
// pq := &temp
// heap.Init(pq)
// heap.Push(pq, &Node{pri: intValue})
// popped := heap.Pop(pq).(*Node)

// MODはとったか？
// 遷移だけじゃなくて最後の最後でちゃんと取れよ？

/*******************************************************************/


Measured memory_bytes: 13056