#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")
#include <bits/stdc++.h>
#include <string>
#include <iostream>
#include <cmath>
#include <numeric>
#include <stack>
#include <queue>
#include <set>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<pi>> vvpi;
typedef vector<ld> vd;
typedef vector<long long> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
#define FOR(i, a, b) for (int i = a; i < (b); i++)
#define F0R(i, a) for (int i = 0; i < (a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto &a : x)
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
#define len(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define F first
#define nl endl
#define S second
#define lb lower_bound
#define ub upper_bound
#define aint(x) x.begin(), x.end()
#define raint(x) x.rbegin(), x.rend()
#define ins insert
const int M = 1e9+7;
void init(string name)
{
freopen((name + ".in").c_str(), "r", stdin);
freopen((name + ".out").c_str(), "w", stdout);
}
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
}
int n,q;
vector<pair<pi,int>> arr;
vvi paths(1e5+5);
void solve()
{
cin >> n >> q;
FOR(i,0,n){
int a,b;cin >> a >> b;
arr.pb({{b,a},i+1});
}
sort(arr.rbegin(),arr.rend());
FOR(i,0,n){
FOR(j,0,n){
if(i == j)continue;
// cerr << i << " " << j << " " << arr[j].F.F << " " << arr[i].F.S << " " << arr[i].F.F << endl;
if(arr[i].F.S <= arr[j].F.F && arr[i].F.F >= arr[j].F.F){
paths[arr[j].S].pb(arr[i].S);
}
// else{
// if(j>i)break;
// }
}
}
// FOR(i,1,n+1){
// cerr << i << " -> ";
// for(int j:paths[i])cerr << j << " ";
// cerr << endl;
// }cerr << endl;
FOR(i,0,q){
int a,b;cin >> a >> b;
vi visited(n+2,0);
vi dist(n+2,1e9);
priority_queue<pi> pq;
pq.push({0,a});
dist[a] = 0;
while(!pq.empty()){
int c = pq.top().S;pq.pop();
if(visited[c])continue;
visited[c] = 1;
for(int d:paths[c]){
if(dist[d] > dist[c] + 1){
dist[d] = dist[c] + 1;
pq.push({-dist[d],d});
}
}
}
// FOR(i,1,n+1){
// cerr << dist[i] << " ";
// }cerr << endl;
if(dist[b] == 1e9)cout << "impossible" << endl;
else cout << dist[b] << endl;
}
}
int main()
{
fastIO();
// init("test");
int t = 1;
// cin >> t;
while (t--)
solve();
return 0;
}
Compilation message
events.cpp: In function 'void init(std::string)':
events.cpp:45:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
45 | freopen((name + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
events.cpp:46:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
46 | freopen((name + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Execution timed out |
1591 ms |
4396 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Correct |
1 ms |
2652 KB |
Output is correct |
3 |
Correct |
4 ms |
2844 KB |
Output is correct |
4 |
Correct |
3 ms |
2652 KB |
Output is correct |
5 |
Correct |
3 ms |
2652 KB |
Output is correct |
6 |
Correct |
8 ms |
3676 KB |
Output is correct |
7 |
Correct |
17 ms |
4532 KB |
Output is correct |
8 |
Correct |
22 ms |
5464 KB |
Output is correct |
9 |
Correct |
81 ms |
6924 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Correct |
1 ms |
2652 KB |
Output is correct |
3 |
Correct |
4 ms |
2844 KB |
Output is correct |
4 |
Correct |
3 ms |
2652 KB |
Output is correct |
5 |
Correct |
3 ms |
2652 KB |
Output is correct |
6 |
Correct |
8 ms |
3676 KB |
Output is correct |
7 |
Correct |
17 ms |
4532 KB |
Output is correct |
8 |
Correct |
22 ms |
5464 KB |
Output is correct |
9 |
Correct |
81 ms |
6924 KB |
Output is correct |
10 |
Correct |
2 ms |
2908 KB |
Output is correct |
11 |
Correct |
1 ms |
2812 KB |
Output is correct |
12 |
Correct |
4 ms |
2652 KB |
Output is correct |
13 |
Correct |
4 ms |
2880 KB |
Output is correct |
14 |
Correct |
3 ms |
2652 KB |
Output is correct |
15 |
Correct |
10 ms |
3672 KB |
Output is correct |
16 |
Correct |
18 ms |
4624 KB |
Output is correct |
17 |
Correct |
20 ms |
5568 KB |
Output is correct |
18 |
Correct |
84 ms |
6748 KB |
Output is correct |
19 |
Execution timed out |
1553 ms |
33672 KB |
Time limit exceeded |
20 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Correct |
1 ms |
2652 KB |
Output is correct |
3 |
Correct |
4 ms |
2844 KB |
Output is correct |
4 |
Correct |
3 ms |
2652 KB |
Output is correct |
5 |
Correct |
3 ms |
2652 KB |
Output is correct |
6 |
Correct |
8 ms |
3676 KB |
Output is correct |
7 |
Correct |
17 ms |
4532 KB |
Output is correct |
8 |
Correct |
22 ms |
5464 KB |
Output is correct |
9 |
Correct |
81 ms |
6924 KB |
Output is correct |
10 |
Correct |
1 ms |
2648 KB |
Output is correct |
11 |
Correct |
1 ms |
2652 KB |
Output is correct |
12 |
Correct |
4 ms |
2652 KB |
Output is correct |
13 |
Correct |
3 ms |
2652 KB |
Output is correct |
14 |
Correct |
4 ms |
2648 KB |
Output is correct |
15 |
Correct |
9 ms |
3672 KB |
Output is correct |
16 |
Correct |
20 ms |
4444 KB |
Output is correct |
17 |
Correct |
19 ms |
5464 KB |
Output is correct |
18 |
Correct |
81 ms |
6748 KB |
Output is correct |
19 |
Execution timed out |
1550 ms |
6340 KB |
Time limit exceeded |
20 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1518 ms |
4560 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2652 KB |
Output is correct |
2 |
Execution timed out |
1591 ms |
4396 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |