oj.uz

Submission #577766

# Submission time Handle Problem Language Result Execution time Memory
577766 2022-06-15T08:46:21 Z vanic Event Hopping (BOI22_events) C++14
10 / 100
 1500 ms 41760 KB 
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <cstring>
 
using namespace std;
 
const int maxn=1e5+5;
 
vector < int > svi;
 
void query(int l, int d){
	for(l+=maxn, d+=maxn; l<d; l>>=1, d>>=1){
		if(l&1){
			svi.push_back(l++);
		}
		if(d&1){
			svi.push_back(--d);
		}
	}
/*	if(L>=l && D<=d){
		svi.push_back(x);
		return;
	}
	if((L+D)/2>=l){
		query(L, (L+D)/2, x*2, l, d);
	}
	if((L+D)/2+1<=d){
		query((L+D)/2+1, D, x*2+1, l, d);
	}*/
}
 
 
pair < int, int > a[maxn];
set < int > s;
map < int, int > m;
int dist[maxn*2];
int d[maxn];
vector < pair < int, int > >  ms[maxn*2];
 
void precompute(){
	for(int i=2; i<maxn*2; i++){
		ms[i].push_back({i/2, 0});
	}
}
 
void bfs(int x){
	memset(dist, -1, sizeof(dist));
	memset(d, -1, sizeof(d));
	vector < int > q1, q2;
	q1.push_back(a[x].second+maxn);
	dist[a[x].second+maxn]=0;
	d[x]=0;
	int tren=0;
	while(!q1.empty()){
		while(!q1.empty()){
			x=q1.back();
			q1.pop_back();
			for(int i=0; i<(int)ms[x].size(); i++){
				if(ms[x][i].second){
					if(dist[ms[x][i].first]==-1){
						dist[ms[x][i].first]=tren+1;
						q2.push_back(ms[x][i].first);
					}
					if(d[ms[x][i].second]==-1){
						d[ms[x][i].second]=tren+1;
					}
				}
				else{
					if(dist[ms[x][i].first]==-1){
						dist[ms[x][i].first]=tren;
						q1.push_back(ms[x][i].first);
					}
				}
			}
		}
		swap(q1, q2);
		tren++;
	}
}
 
int main(){
	precompute();
	int n, q;
	scanf("%d%d", &n, &q);
	for(int i=1; i<=n; i++){
		scanf("%d%d", &a[i].first, &a[i].second);
		s.insert(a[i].second);
	}
	int br=0;
	
	for(auto it=s.begin(); it!=s.end(); it++){
		m[*it]=br;
		br++;
	}
	set < int >::iterator it;
	for(int i=1; i<=n; i++){
		it=s.lower_bound(a[i].first);
		a[i]={m[*it], m[a[i].second]};
//		cout << a[i].first << ' ' << a[i].second << endl;
		query(a[i].first, a[i].second+1);
		while(!svi.empty()){
//			cout << "moji " << svi.back() << endl;
			ms[svi.back()].push_back({a[i].second+maxn, i});
			svi.pop_back();
		}
	}
	int x, y;
	for(int i=0; i<q; i++){
		scanf("%d%d", &x, &y);
		bfs(x);
		if(d[y]==-1){
			printf("impossible\n");
		}
		else{
			printf("%d\n", d[y]);
		}
	}
	return 0;
}

Compilation message

events.cpp: In function 'int main()':
events.cpp:88:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |  scanf("%d%d", &n, &q);
      |  ~~~~~^~~~~~~~~~~~~~~~
events.cpp:90:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |   scanf("%d%d", &a[i].first, &a[i].second);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
events.cpp:113:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |   scanf("%d%d", &x, &y);
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 12372 KB Output is correct
2 Execution timed out 1586 ms 22696 KB Time limit exceeded
3 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12372 KB Output is correct
2 Correct 13 ms 12392 KB Output is correct
3 Correct 21 ms 12416 KB Output is correct
4 Correct 18 ms 12500 KB Output is correct
5 Correct 19 ms 12456 KB Output is correct
6 Correct 16 ms 12516 KB Output is correct
7 Correct 20 ms 12644 KB Output is correct
8 Correct 20 ms 12664 KB Output is correct
9 Correct 16 ms 12468 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12372 KB Output is correct
2 Correct 13 ms 12392 KB Output is correct
3 Correct 21 ms 12416 KB Output is correct
4 Correct 18 ms 12500 KB Output is correct
5 Correct 19 ms 12456 KB Output is correct
6 Correct 16 ms 12516 KB Output is correct
7 Correct 20 ms 12644 KB Output is correct
8 Correct 20 ms 12664 KB Output is correct
9 Correct 16 ms 12468 KB Output is correct
10 Correct 12 ms 12372 KB Output is correct
11 Correct 12 ms 12348 KB Output is correct
12 Correct 21 ms 12524 KB Output is correct
13 Correct 19 ms 12424 KB Output is correct
14 Correct 17 ms 12548 KB Output is correct
15 Correct 19 ms 12524 KB Output is correct
16 Correct 19 ms 12628 KB Output is correct
17 Correct 21 ms 12628 KB Output is correct
18 Correct 16 ms 12372 KB Output is correct
19 Execution timed out 1587 ms 13548 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12372 KB Output is correct
2 Correct 13 ms 12392 KB Output is correct
3 Correct 21 ms 12416 KB Output is correct
4 Correct 18 ms 12500 KB Output is correct
5 Correct 19 ms 12456 KB Output is correct
6 Correct 16 ms 12516 KB Output is correct
7 Correct 20 ms 12644 KB Output is correct
8 Correct 20 ms 12664 KB Output is correct
9 Correct 16 ms 12468 KB Output is correct
10 Correct 11 ms 12372 KB Output is correct
11 Correct 12 ms 12376 KB Output is correct
12 Correct 20 ms 12420 KB Output is correct
13 Correct 16 ms 12500 KB Output is correct
14 Correct 19 ms 12512 KB Output is correct
15 Correct 17 ms 12528 KB Output is correct
16 Correct 19 ms 12564 KB Output is correct
17 Correct 18 ms 12600 KB Output is correct
18 Correct 18 ms 12372 KB Output is correct
19 Correct 977 ms 22704 KB Output is correct
20 Correct 657 ms 22596 KB Output is correct
21 Correct 603 ms 23248 KB Output is correct
22 Correct 364 ms 22584 KB Output is correct
23 Correct 1466 ms 41760 KB Output is correct
24 Execution timed out 1577 ms 34088 KB Time limit exceeded
25 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1569 ms 22568 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 12372 KB Output is correct
2 Execution timed out 1586 ms 22696 KB Time limit exceeded
3 Halted 0 ms 0 KB -