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Submission #588689

# Submission time Handle Problem Language Result Execution time Memory
588689 2022-07-03T21:09:48 Z peuch Event Hopping (BOI22_events) C++17
25 / 100
 274 ms 524288 KB 
#include<bits/stdc++.h>
using namespace std;

const int MAXN = 1e5 + 10;
const int INF = 1e9;

int n, q;
int s[MAXN], e[MAXN];
int ans[MAXN];

struct event{
	int s, e, id;
	event(int _s, int _e, int _id) {
		s = _s;
		e = _e;
		id = _id;
	}
	bool operator < (event x){
		if(e == x.e) return s < x.s;
		return e < x.e;
	}
};

struct query{
	int l, r, id;
	query(int _l, int _r, int _id){
		l = _l;
		r = _r;
		id = _id;
	}
};

vector<query> ar[MAXN];

vector<event> line;
vector<int> dist[MAXN];

int main(){
	scanf("%d %d", &n, &q);
	for(int i = 1; i <= n; i++){
		scanf("%d %d", &s[i], &e[i]);
		line.push_back(event(s[i], e[i], i));
	}
	for(int i = 1; i <= q; i++){
		int ini, fim;
		scanf("%d %d", &ini, &fim);
		ans[i] = INF;
		if(ini == fim) ans[i] = 0;
		else ar[fim].push_back(query(e[ini], e[fim], i));
	}
	
	sort(line.begin(), line.end());
	
	vector<int> pilha;
	for(int i = 0; i < line.size(); i++){
//		printf("Adding event: %d %d\n", line[i].s, line[i].e);
		while(!pilha.empty() && line[pilha.back()].s >= line[i].s){
			pilha.pop_back();
		}
		pilha.push_back(i);
		
		int ini = 0, fim = pilha.size() - 1;
		while(ini != fim){
			int mid = (ini + fim) >> 1;
			if(line[pilha[mid]].e >= line[i].s) fim = mid;
			else ini = mid + 1;
		}
		ini = pilha[ini];
//		printf("\t -> %d\n", ini);
		dist[i] = dist[ini];
		dist[i].push_back(line[i].s);
//		printf("\t");
//		for(int j = 0; j < dist[i].size(); j++)
//			printf("%d ", dist[i][j]);
//		printf("\n");
		for(int j = 0; j < ar[line[i].id].size(); j++){
//			printf("Query event: %d %d %d\n", ar[line[i].id][j].l, ar[line[i].id][j].r, ar[line[i].id][j].id);
			if(ar[line[i].id][j].l > ar[line[i].id][j].r) continue;
			int k = upper_bound(dist[i].begin(), dist[i].end(), ar[line[i].id][j].l) - dist[i].begin() - 1;
//			printf("\t%d\n", k);
			if(k < 0) continue;
			ans[ar[line[i].id][j].id] = dist[i].size() - k;
		}
//		for(int j = 0; j <= i; j++){
//			printf("dist[%d] = ", j);
//			for(int k = 0; k < dist[j].size(); k++)
//				printf("%d ", dist[j][k]);
//			printf("\n");
//		}
	}
	
	for(int i = 1; i <= q; i++){
		if(ans[i] == INF) printf("impossible\n");
		else printf("%d\n", ans[i]);
	}
}

Compilation message

events.cpp: In function 'int main()':
events.cpp:55:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<event>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |  for(int i = 0; i < line.size(); i++){
      |                 ~~^~~~~~~~~~~~~
events.cpp:76:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<query>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |   for(int j = 0; j < ar[line[i].id].size(); j++){
      |                  ~~^~~~~~~~~~~~~~~~~~~~~~~
events.cpp:39:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |  scanf("%d %d", &n, &q);
      |  ~~~~~^~~~~~~~~~~~~~~~~
events.cpp:41:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |   scanf("%d %d", &s[i], &e[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~
events.cpp:46:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |   scanf("%d %d", &ini, &fim);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Runtime error 274 ms 524288 KB Execution killed with signal 9
3 Halted 0 ms 0 KB -

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 5 ms 9384 KB Output is correct
4 Correct 4 ms 7124 KB Output is correct
5 Correct 7 ms 9428 KB Output is correct
6 Correct 3 ms 5076 KB Output is correct
7 Correct 3 ms 5048 KB Output is correct
8 Correct 4 ms 5080 KB Output is correct
9 Correct 4 ms 5076 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 5 ms 9384 KB Output is correct
4 Correct 4 ms 7124 KB Output is correct
5 Correct 7 ms 9428 KB Output is correct
6 Correct 3 ms 5076 KB Output is correct
7 Correct 3 ms 5048 KB Output is correct
8 Correct 4 ms 5080 KB Output is correct
9 Correct 4 ms 5076 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 6 ms 9428 KB Output is correct
13 Correct 4 ms 7088 KB Output is correct
14 Correct 5 ms 9428 KB Output is correct
15 Correct 3 ms 4948 KB Output is correct
16 Correct 3 ms 5076 KB Output is correct
17 Correct 3 ms 5040 KB Output is correct
18 Correct 3 ms 5044 KB Output is correct
19 Correct 59 ms 54448 KB Output is correct
20 Correct 74 ms 87672 KB Output is correct
21 Correct 85 ms 88100 KB Output is correct
22 Correct 31 ms 9320 KB Output is correct
23 Correct 32 ms 8880 KB Output is correct
24 Correct 33 ms 8852 KB Output is correct
25 Correct 33 ms 9552 KB Output is correct

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Correct 5 ms 9384 KB Output is correct
4 Correct 4 ms 7124 KB Output is correct
5 Correct 7 ms 9428 KB Output is correct
6 Correct 3 ms 5076 KB Output is correct
7 Correct 3 ms 5048 KB Output is correct
8 Correct 4 ms 5080 KB Output is correct
9 Correct 4 ms 5076 KB Output is correct
10 Correct 4 ms 4972 KB Output is correct
11 Correct 4 ms 4948 KB Output is correct
12 Correct 6 ms 9428 KB Output is correct
13 Correct 5 ms 7084 KB Output is correct
14 Correct 6 ms 9400 KB Output is correct
15 Correct 3 ms 5076 KB Output is correct
16 Correct 3 ms 5076 KB Output is correct
17 Correct 3 ms 5024 KB Output is correct
18 Correct 4 ms 5076 KB Output is correct
19 Runtime error 237 ms 524288 KB Execution killed with signal 9
20 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory Grader output
1 Runtime error 271 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Runtime error 274 ms 524288 KB Execution killed with signal 9
3 Halted 0 ms 0 KB -