#include <bits/stdc++.h>
#define mp make_pair
#define eb emplace_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define svec(x) sort(all(x))
#define press(x) x.erase(unique(all(x)), x.end());
using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
typedef pair<int, LL> pil;
typedef pair<LL, int> pli;
typedef pair<LL, LL> pll;
const int INF=1e9;
const LL LLINF=1e18;
int n, k, m, q, l[100010], r[100010];
multiset<int> ms;
vector<int> vcl[100010], vcr[100010];
struct SEG{
pii tree[400010];
pii func(pii a, pii b){return mp(min(a.F, b.F), max(a.S, b.S));}
void upd(int point, int s, int e, int num, pii val){
if(s==e){
tree[point]=val;
return;
}
if(num<=(s+e)/2)upd(point*2, s, (s+e)/2, num, val);
else upd(point*2+1, (s+e)/2+1, e, num, val);
tree[point]=func(tree[point*2], tree[point*2+1]);
}
pii query(int point, int s, int e, int a, int b){
if(e<a||s>b)return mp(INF, 0);
if(a<=s&&e<=b)return tree[point];
return func(query(point*2, s, (s+e)/2, a, b), query(point*2+1, (s+e)/2+1, e, a, b));
}
}seg[19];
int main(){
scanf("%d %d %d", &n, &k, &m);
for(int i=1; i<=m; i++){
int a, b;
scanf("%d %d", &a, &b);
if(a<b)vcl[a].eb(b);
else vcr[a].eb(b);
}
for(int i=1; i<=n; i++){
for(auto j:vcl[i])ms.insert(j);
r[i]=i;
if(ms.size())r[i]=*ms.rbegin();
if(i>=k){
for(auto j:vcl[i-k+1])ms.erase(j);
}
}
ms.clear();
for(int i=n; i>=1; i--){
for(auto j:vcr[i])ms.insert(j);
l[i]=i;
if(ms.size())l[i]=*ms.begin();
if(i<=n-k+1){
for(auto j:vcr[i+k-1])ms.erase(j);
}
}
for(int i=1; i<=n; i++)seg[0].upd(1, 1, n, i, mp(l[i], r[i]));
for(int i=1; i<=18; i++){
for(int j=1; j<=n; j++){
pii tmp=seg[i-1].query(1, 1, n, j, j);
seg[i].upd(1, 1, n, j, seg[i-1].query(1, 1, n, tmp.F, tmp.S));
}
}
scanf("%d", &q);
for(int i=1; i<=q; i++){
int a, b, ans=0;
scanf("%d %d", &a, &b);
pii r=mp(a, a);
for(int j=18; j>=0; j--){
pii r2=seg[j].query(1, 1, n, r.F, r.S);
if(b<r2.F||b>r2.S)r=r2, ans+=(1<<j);
}
else if(ans>n)puts("-1");
else printf("%d\n", ans+1);
}
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:82:9: error: 'else' without a previous 'if'
82 | else if(ans>n)puts("-1");
| ^~~~
Main.cpp:42:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
42 | scanf("%d %d %d", &n, &k, &m);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:45:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
45 | scanf("%d %d", &a, &b);
| ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:73:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
73 | scanf("%d", &q);
| ~~~~~^~~~~~~~~~
Main.cpp:76:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
76 | scanf("%d %d", &a, &b);
| ~~~~~^~~~~~~~~~~~~~~~~
