#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define thuhien ""
#define re exit(0);
const int maxm = 200009;
const int maxn = 100009;
const int LOG = 16;
inline pair <int,int> merge(pair <int,int> a,pair <int,int> b) {
return {min(a.first,b.first),max(a.second,b.second)};
}
int n,k,m;
pair <int,int> line[maxm];
int q;
//segment tree
struct SegmentTree {
pair <int,int> st[maxn * 4];
void build(int id,int l,int r,pair <int,int> arr[]) {
if (l == r) {
st[id] = arr[l];
return;
}
int mid = (l + r) >> 1;
build(id*2,l,mid,arr);
build(id*2+1,mid+1,r,arr);
st[id] = merge(st[id*2],st[id*2+1]);
}
pair <int,int> get(int id,int l,int r,int u,int v) {
if (l >= u && r <= v) return st[id];
int mid = (l + r) >> 1;
if (v <= mid) return get(id*2,l,mid,u,v);
else if (u > mid) return get(id*2+1,mid+1,r,u,v);
return merge(get(id*2,l,mid,u,v),get(id*2+1,mid+1,r,u,v));
}
};
SegmentTree jump[LOG + 1];
pair <int,int> TEMP[maxn];
//create reach
pair <int,int> st[maxn * 4];
void add(int id,int l,int r,int u,int v,pair <int,int> val) {
if (l > v || r < u) return;
if (l >= u && r <= v) {
st[id] = merge(st[id],val);
return;
}
int mid = (l + r) >> 1;
add(id*2,l,mid,u,v,val);
add(id*2+1,mid+1,r,u,v,val);
}
void dfs(int id,int l,int r) {
if (l == r) {
TEMP[l] = merge(st[id],{l,l});
return;
}
int mid = (l + r) >> 1;
st[id*2] = merge(st[id*2],st[id]);
st[id*2+1] = merge(st[id*2+1],st[id]);
dfs(id*2,l,mid);
dfs(id*2+1,mid+1,r);
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(nullptr);
if (fopen(thuhien".inp","r")) {
freopen(thuhien".inp","r",stdin);
freopen(thuhien".out","w",stdout);
}
cin >> n >> k >> m;
for (int i = 1;i <= 4*n;i++) st[i] = {1e9,-1e9};
for (int i = 1;i <= m;i++) {
cin >> line[i].first >> line[i].second;
if (line[i].first < line[i].second) {
add(1,1,n,line[i].first,min(line[i].first + k - 1,line[i].second - 1),{1e9,line[i].second});
} else {
add(1,1,n,max(line[i].first - k + 1,line[i].second + 1),line[i].first,{line[i].second,-1e9});
}
}
dfs(1,1,n);
jump[0].build(1,1,n,TEMP);
for (int j = 1;j <= LOG;j++) {
for (int i = 1;i <= n;i++) {
pair <int,int> seg = jump[j - 1].get(1,1,n,i,i);
TEMP[i] = jump[j - 1].get(1,1,n,seg.first,seg.second);
}
jump[j].build(1,1,n,TEMP);
}
cin >> q;
while (q--) {
int s,t;cin >> s >> t;
int res = 0,l = s,r = s;
for (int i = LOG;i >= 0;i--) {
pair <int,int> damn = jump[i].get(1,1,n,l,r);
if (damn.first > t || damn.second < t) {
res += 1 << i;
l = damn.first;
r = damn.second;
}
}
res++;
cout << (res > n ? -1 : res) << '\n';
}
}
