#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const int MAXN = 1e5 + 10;
struct Node {
int mi = INF, mx = -INF;
};
Node join(const Node& a, const Node& b) {
Node ans;
ans.mi = min(a.mi, b.mi);
ans.mx = max(a.mx, b.mx);
return ans;
}
Node empt;
struct SegTree {
Node seg[4*MAXN];
int lazyMi[4*MAXN];
int lazyMx[4*MAXN];
void build(int node, int l, int r) {
lazyMx[node] = -INF;
lazyMi[node] = INF;
if (l == r) {
seg[node].mi = seg[node].mx = l;
return;
}
int m = (l + r)/2;
build(2*node, l, m);
build(2*node + 1, m + 1, r);
seg[node] = join(seg[2*node], seg[2*node + 1]);
}
void unlazy(int node, int l, int r) {
// do lazymi
if (lazyMi[node] != INF) {
seg[node].mi = min(seg[node].mi, lazyMi[node]);
if (l < r) {
lazyMi[2*node] = min(lazyMi[2*node], lazyMi[node]);
lazyMi[2*node + 1] = min(lazyMi[2*node + 1], lazyMi[node]);
}
lazyMi[node] = INF;
}
if (lazyMx[node] != (-INF)) {
seg[node].mx = max(seg[node].mx, lazyMx[node]);
if (l < r) {
lazyMx[2*node] = max(lazyMx[2*node], lazyMx[node]);
lazyMx[2*node + 1] = max(lazyMx[2*node + 1], lazyMx[node]);
}
lazyMx[node] = (-INF);
}
}
void update(int node, int l, int r, int tl, int tr, int val) {
unlazy(node, l, r);
if ((r < tl) || (tr < l)) return;
if ((tl <= l) && (r <= tr)) {
lazyMi[node] = min(lazyMi[node], val);
lazyMx[node] = max(lazyMx[node], val);
unlazy(node, l, r);
return;
}
int m = (l+r)/2;
update(2*node, l, m, tl, tr, val);
update(2*node + 1, m + 1, r, tl, tr, val);
seg[node] = join(seg[2*node], seg[2*node + 1]);
}
Node query(int node, int l, int r, int tl, int tr) {
unlazy(node, l, r);
if ((r < tl) || (tr < l)) return empt;
if ((tl <= l) && (r <= tr)) return seg[node];
int m = (l+r)/2;
return join(query(2*node, l, m, tl, tr), query(2*node + 1, m + 1, r, tl, tr));
}
};
bool inRange(int a, int l, int r) {
return ((l <= a) && (a <= r));
}
const int MAXLOG = 18;
SegTree layer[MAXLOG];
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int n, k, m, q;
cin >> n >> k >> m;
layer[0].build(1, 1, n);
for (int i = 1; i <= m; i++) {
int a, b;
cin >> a >> b;
if (a < b) {
int upTo = min(a + k - 1, b - 1);
layer[0].update(1, 1, n, a, upTo, b);
} else {
int upTo = max(a - k + 1, b + 1);
layer[0].update(1, 1, n, upTo, a, b);
}
}
for (int l = 1; l < MAXLOG; l++) {
layer[l].build(1, 1, n);
for (int i = 1; i <= n; i++) {
Node r = layer[l - 1].query(1, 1, n, i, i);
Node novo = layer[l - 1].query(1, 1, n, r.mi, r.mx);
layer[l].update(1, 1, n, i, i, novo.mi);
layer[l].update(1, 1, n, i, i, novo.mx);
}
}
cin >> q;
while (q--) {
int s, t;
cin >> s >> t;
// check if its -1
Node ult = layer[MAXLOG - 1].query(1, 1, n, s, s);
if (!inRange(t, ult.mi, ult.mx)) {
cout << "-1\n";
continue;
}
int mult = 1;
for (int i = 0; i < (MAXLOG - 1); i++) {
mult <<= 1;
}
int minAns = INF;
int curr = 0;
int l = s, r = s;
for (int i = MAXLOG - 1; i >= 0; i--) {
Node can = layer[i].query(1, 1, n, l, r);
if (!inRange(t, can.mi, can.mx)) {
l = can.mi;
r = can.mx;
curr += mult;
} else {
minAns = min(minAns, curr + mult);
}
mult >>= 1;
}
cout << minAns << "\n";
}
}
