### BUGGY CODE ###

import sys
sys.setrecursionlimit(10**9)
input = lambda: sys.stdin.readline().rstrip()
inpl = lambda: list(map(int,input().split()))
N, M, L = inpl()
road = [[] for _ in range(N)]
for i in range(M):
    A, B, C = inpl()
    if C <= L:
        road[A-1].append((B-1,C))
        road[B-1].append((A-1,C))
minimum = [ [(-1,0)]*N for _ in range(N)]
for i in range(N):
    minimum[i][i] = (0,0)

Q = int(input())
ST = [inpl() for _ in range(Q)]
starts = set([ s-1 for s,t in ST])
for start in starts:
    prev = {start}
    while prev:
        cur = set()
        for p in prev:
            for q, c in road[p]:
                pn, pred = minimum[start][p]
                qn, qred = minimum[start][q]
                if pred + c > L:
                    qn2, qred2 = pn + 1, c
                else:
                    qn2, qred2 = pn, pred + c
                if qn < 0 or qn2 < qn or (qn2==qn and qred2 < qred):
                    minimum[start][q] = qn2, qred2
                    cur.add(q)
        prev = cur

for s,t in ST:
    print(minimum[s-1][t-1][0])

### FIXED CODE ###

import sys
sys.setrecursionlimit(10**9)
input = lambda: sys.stdin.readline().rstrip()
inpl = lambda: list(map(int,input().split()))

class SegmentTree:
    def __init__(self, value=[], N=0, comp=lambda x,y: x<=y, reverse=False):
        M = max(len(value),N)
        N = 2**(len(bin(M))-3)
        if N < M: N *= 2
        self.N = N
        self.node = [0] * (2*N-1)
        for i in range(N):
            self.node[N-1+i] = i
        self.value = [None] * N
        for i, v in enumerate(value):
            self.value[i] = v
        self.comp = lambda x, y: True if y is None else False if x is None else comp(x,y)^reverse
        for i in range(N-2,-1,-1):
            left_i, right_i = self.node[2*i+1], self.node[2*i+2]
            left_v, right_v = self.value[left_i], self.value[right_i]
            self.node[i] = left_i if self.comp(left_v, right_v) else right_i

    def update(self, n, v):
        self.value[n] = v
        i = (self.N-1) + n
        while i > 0:
            i = (i-1)//2
            left_i, right_i = self.node[2*i+1], self.node[2*i+2]
            left_v, right_v = self.value[left_i], self.value[right_i]
            new_i = left_i if self.comp(left_v, right_v) else right_i
            if new_i == self.node[i] and new_i != n:
                break
            else:
                self.node[i] = new_i

    def at(self, n):
        if n is None:
            return None
        else:
            return self.value[n]

    def query(self, l=0, r=-1):
        return self.at(self.query_index(l,r))

    def query_index(self, l=0, r=-1):
        if r < 0: r = self.N
        L = l + self.N; R = r + self.N
        s = None
        while L < R:
            if R & 1:
                R -= 1
                if self.comp(self.at(self.node[R-1]), self.at(s)):
                    s = self.node[R-1]
            if L & 1:
                if self.comp(self.at(self.node[L-1]), self.at(s)):
                    s = self.node[L-1]
                L += 1
            L >>= 1; R >>= 1
        return s

N, M, L = inpl()
road = [[] for _ in range(N)]
for i in range(M):
    A, B, C = inpl()
    if C <= L:
        road[A-1].append((B-1,C))
        road[B-1].append((A-1,C))
minimum = [ [-1]*N for _ in range(N)]
for i in range(N):
    minimum[i][i] = 0

INF = 10**4
Q = int(input())
ST = [inpl() for _ in range(Q)]
starts = set([ s-1 for s,t in ST])
segtree = SegmentTree(N=N)
for start in starts:
    for i in range(N):
        segtree.update(i, (INF,0))
    segtree.update(start, (0,0))
    while True:
        p = segtree.query_index()
        pnred = segtree.at(p)
        if pnred is None:
            break
        else:
            pn, pred = pnred
            if pn >= INF:
                break
        minimum[start][p] = pn
        segtree.update(p, None)

        for q, c in road[p]:
            if segtree.at(q) is None:
                continue
            else:
                qn, qred = segtree.at(q)
            if pred + c > L:
                qn2, qred2 = pn + 1, c
            else:
                qn2, qred2 = pn, pred + c
            if qn < 0 or (qn2,qred2) < (qn,qred):
                segtree.update(q, (qn2, qred2))

for s,t in ST:
    print(minimum[s-1][t-1])