// Code by Parsa Eslami
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast,O3,unroll-loops")
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
#define bit(i,j) ((j>>i)&1)
#define minm(x,y) x=min(x,y)
#define maxm(x,y) x=max(x,y)
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORR(i,a,b) for(int i=a;i>=b;i--)
#define S second
#define F first
#define pb push_back
#define SZ(x) (int)x.size()
#define all(x) x.begin(),x.end()
#define err(x) cout<<#x<<": "<<x<<'\n'
#define wtf cout<<"WHAT THE FUCK!\n"
#define dmid int mid=(r+l)/2
#define lc 2*id
#define rc 2*id+1
using namespace std;
const int inf=1e9;
const int N=2e5+4;
const int SQ=0;
const int lg=20;
int fen[N],S[N],E[N],ans[N],nxt[lg][N],rnk[N];
pii xy[N];
bool mark[N];
vector<int> vc;
int n,q;
int mnS;
void upd(int k,int x){
while(k<N){
maxm(fen[k],x);
k+=(k&(-k));
}
}
int get(int k){
int rt=0;
while(k>0){
maxm(rt,fen[k]);
k-=(k&(-k));
}
return rt;
}
bool cmp(int i,int j){
if(xy[i].S!=xy[j].S) return (xy[i].S<xy[j].S);
return (xy[i].F<xy[j].F);
}
bool adj(int u,int v){
return (E[u]>=S[v]&&E[u]<=E[v]);
}
void relax(){
for(int v:vc) mark[v]=1;
vc.clear();
FOR(i,1,n) if(mark[i]){
nxt[0][i]=get(E[i]);
if(nxt[0][i]==i) nxt[0][i]=0;
}
FOR(j,1,lg-1) FOR(i,1,n) nxt[j][i]=nxt[j-1][nxt[j-1][i]];
mnS=inf;
}
void ADD(int v){
if(SZ(vc)>=SQ) relax();
for(int u:vc) if(adj(u,v)) nxt[0][u]=v;
vc.pb(v);
upd(S[v],v);
minm(mnS,S[v]);
}
int go(int u,int v){
if(adj(u,v)) return 0;
int NXT=0;
if(nxt[0][u]==0) NXT=get(E[u]);
else NXT=nxt[0][u];
if(NXT==u) NXT=0;
if(NXT==0) return inf;
return (go(NXT,v)+1);
}
int dis(int u,int v){
if(adj(u,v)) return 0;
if(!mark[u]) return go(u,v);
int rt=0;
FORR(j,lg-1,0){
if(nxt[j][u]!=0&&E[nxt[j][u]]<min(mnS,S[v])) rt+=(1<<j),u=nxt[j][u];
}
return min(inf,go(u,v)+rt);
}
int32_t main(){
ios_base::sync_with_stdio(0); cin.tie(0);
mnS=1e9;
cin>>n>>q;
FOR(i,1,n) cin>>xy[i].F>>xy[i].S;
vector<pair<int,pii>> vz;
FOR(i,1,n) vz.pb({xy[i].F,{i,0}}),vz.pb({xy[i].S,{i,1}});
sort(all(vz));
int bv=0;
FOR(i,0,SZ(vz)-1){
if(i==0||vz[i].F!=vz[i-1].F) bv++;
if(vz[i].S.S==0) xy[vz[i].S.F].F=bv;
else xy[vz[i].S.F].S=bv;
}
int RNK[n+1];
FOR(i,1,n) RNK[i]=i;
sort(RNK+1,RNK+n+1,cmp);
FOR(i,1,n) rnk[RNK[i]]=i;
FOR(i,1,n) E[rnk[i]]=xy[i].S;
FOR(i,1,n) S[rnk[i]]=xy[i].F;
vector<pair<pii,pii>> Q;
FOR(i,1,q){
int s,e; cin>>s>>e;
Q.pb({{rnk[e],i},{rnk[s],rnk[e]}});
}
sort(all(Q));
int last=1;
FOR(i,0,q-1){
while(last<=Q[i].S.S){
ADD(last);
last++;
}
if(Q[i].S.F==Q[i].S.S){ ans[Q[i].F.S-1]=0; continue;}
if(Q[i].S.F>Q[i].S.S){
if(E[Q[i].S.F]==E[Q[i].S.S]) ans[Q[i].F.S-1]=1;
else ans[Q[i].F.S-1]=inf;
continue;
}
ans[Q[i].F.S-1]=dis(Q[i].S.F,Q[i].S.S)+1;
}
FOR(i,0,q-1){
if(ans[i]>=inf) cout<<"impossible"; else cout<<ans[i];
cout<<'\n';
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
468 KB |
Output is correct |
2 |
Execution timed out |
1588 ms |
16312 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
468 KB |
Output is correct |
2 |
Correct |
1 ms |
472 KB |
Output is correct |
3 |
Correct |
18 ms |
596 KB |
Output is correct |
4 |
Correct |
18 ms |
652 KB |
Output is correct |
5 |
Correct |
18 ms |
648 KB |
Output is correct |
6 |
Correct |
19 ms |
596 KB |
Output is correct |
7 |
Correct |
20 ms |
596 KB |
Output is correct |
8 |
Correct |
18 ms |
772 KB |
Output is correct |
9 |
Correct |
15 ms |
596 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
468 KB |
Output is correct |
2 |
Correct |
1 ms |
472 KB |
Output is correct |
3 |
Correct |
18 ms |
596 KB |
Output is correct |
4 |
Correct |
18 ms |
652 KB |
Output is correct |
5 |
Correct |
18 ms |
648 KB |
Output is correct |
6 |
Correct |
19 ms |
596 KB |
Output is correct |
7 |
Correct |
20 ms |
596 KB |
Output is correct |
8 |
Correct |
18 ms |
772 KB |
Output is correct |
9 |
Correct |
15 ms |
596 KB |
Output is correct |
10 |
Correct |
0 ms |
468 KB |
Output is correct |
11 |
Correct |
0 ms |
468 KB |
Output is correct |
12 |
Correct |
18 ms |
596 KB |
Output is correct |
13 |
Correct |
18 ms |
660 KB |
Output is correct |
14 |
Correct |
18 ms |
596 KB |
Output is correct |
15 |
Correct |
19 ms |
656 KB |
Output is correct |
16 |
Correct |
19 ms |
648 KB |
Output is correct |
17 |
Correct |
19 ms |
664 KB |
Output is correct |
18 |
Correct |
13 ms |
648 KB |
Output is correct |
19 |
Correct |
489 ms |
3960 KB |
Output is correct |
20 |
Correct |
472 ms |
3744 KB |
Output is correct |
21 |
Correct |
474 ms |
4116 KB |
Output is correct |
22 |
Correct |
495 ms |
4096 KB |
Output is correct |
23 |
Correct |
527 ms |
4652 KB |
Output is correct |
24 |
Correct |
502 ms |
4584 KB |
Output is correct |
25 |
Correct |
475 ms |
4204 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
468 KB |
Output is correct |
2 |
Correct |
1 ms |
472 KB |
Output is correct |
3 |
Correct |
18 ms |
596 KB |
Output is correct |
4 |
Correct |
18 ms |
652 KB |
Output is correct |
5 |
Correct |
18 ms |
648 KB |
Output is correct |
6 |
Correct |
19 ms |
596 KB |
Output is correct |
7 |
Correct |
20 ms |
596 KB |
Output is correct |
8 |
Correct |
18 ms |
772 KB |
Output is correct |
9 |
Correct |
15 ms |
596 KB |
Output is correct |
10 |
Correct |
0 ms |
468 KB |
Output is correct |
11 |
Correct |
0 ms |
468 KB |
Output is correct |
12 |
Correct |
18 ms |
644 KB |
Output is correct |
13 |
Correct |
19 ms |
596 KB |
Output is correct |
14 |
Correct |
19 ms |
556 KB |
Output is correct |
15 |
Correct |
19 ms |
656 KB |
Output is correct |
16 |
Correct |
20 ms |
636 KB |
Output is correct |
17 |
Correct |
19 ms |
656 KB |
Output is correct |
18 |
Correct |
13 ms |
596 KB |
Output is correct |
19 |
Execution timed out |
1562 ms |
12860 KB |
Time limit exceeded |
20 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1571 ms |
16224 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
468 KB |
Output is correct |
2 |
Execution timed out |
1588 ms |
16312 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |