#include<bits/stdc++.h> using namespace std; #define inf (int)2e9 #define _ <<' '<< #define nl '\n' void solve(){ int n, k, m; cin>>n>>k>>m; vector<int> in[n], out[n]; for(int i = 0; i < m; i++){ int a, b; cin>>a>>b; a--, b--; in[a].push_back(b); out[a < b ? min(b-1, a+k-1) : max(b+1, a-k+1)].push_back(b); } multiset<int> st; int l[n][18], r[n][18]; for(int i = 0; i < n; i++){ for(int b : in[i]){ if(i < b) st.insert(b); } r[i][0] = (st.empty() ? i : *st.rbegin()); for(int b : out[i]){ if(i < b) st.erase(st.find(b)); } } st.clear(); for(int i = n-1; i >= 0; i--){ for(int b : in[i]){ if(i > b) st.insert(b); } l[i][0] = (st.empty() ? i : *st.begin()); for(int b : out[i]){ if(i > b) st.erase(st.find(b)); } } int lg[n+1]; for(int i = 1, p = 1, c = 0; i <= n; i++){ if(p * 2 <= i) p *= 2, c++; lg[i] = c; } int ml[n][18][18], mr[n][18][18]; auto qry = [&](int w, int j, int l, int r){ int c = lg[r-l+1]; if(!w) return min(ml[l][j][c], ml[r - (1<<c) + 1][j][c]); return max(mr[l][j][c], mr[r - (1<<c) + 1][j][c]); }; for(int j = 0; j < 18; j++){ for(int i = 0; i < n; i++){ if(!j) continue; l[i][j] = qry(0, j-1, l[i][j-1], r[i][j-1]); r[i][j] = qry(1, j-1, l[i][j-1], r[i][j-1]); } for(int k = 0; k < 18; k++){ for(int i = 0; i + (1<<k) - 1 < n; i++){ if(k == 0){ ml[i][j][k] = l[i][j]; mr[i][j][k] = r[i][j]; continue; } ml[i][j][k] = min(ml[i][j][k-1], ml[i + (1<<k-1)][j][k-1]); mr[i][j][k] = max(mr[i][j][k-1], mr[i + (1<<k-1)][j][k-1]); } } } int q; cin>>q; while(q--){ int a, b; cin>>a>>b; a--, b--; int cl = a, cr = a, ans = 1; for(int j = 17; j >= 0; j--){ int ncl = qry(0, j, cl, cr); int ncr = qry(1, j, cl, cr); if(ncl <= b and b <= ncr) continue; cl = ncl; cr = ncr; ans += 1<<j; } cout<<(ans > m ? -1 : ans)<<nl; } } signed main(){ ios_base::sync_with_stdio(0); cin.tie(NULL);cout.tie(NULL); int t = 1; //cin>>t; while(t--) solve(); return 0; }