#include <bits/stdc++.h>
using namespace std;
#define int long long
#define nl '\n'
#define pb push_back
#define fore(i , n) for(int i = 0 ; i< n;i++)
#define forr(i , x , y) for(int i = x; i <= y; i++)
#define forn(i , x , y) for(int i = x; i >= y ; i--)
const int N =2e5 + 10;
struct seg
{
int BASE;
vector<int> tree;
void init(int n , vector<int> &a)
{
BASE = n;
while(__builtin_popcount(BASE) != 1)
{
BASE++;
}
tree.assign(2*BASE , N);
fore(i , (int)a.size())
tree[i + BASE] = a[i];
forn(i , BASE - 1 , 1)
tree[i] = min(tree[2*i] , tree[2*i +1]);
}
int query(int l , int r)
{
if(l > r)
return N;
l+=BASE;
r+=BASE;
if(l == r)
return tree[l];
int lt = tree[l] , rt = tree[r];
while(l + 1 < r)
{
if(l %2 == 0)
{
lt = min(lt , tree[l +1]);
}
if(r%2 == 1)
rt = min(tree[r - 1] ,rt);
l>>=1;
r>>=1;
}
return min(lt ,rt);
}
}tree[19];
signed main()
{
int n , q;
cin>>n>>q;
map<int , int> compress;
vector<pair<int ,int>> v(n);
vector<vector<int>> adj(20 , vector<int>(N , N));
vector<tuple<int , int, int>> koll;
fore(i , n)
{
cin>>v[i].first>>v[i].second;
koll.pb({v[i].first , 0 , i});
koll.pb({v[i].second , 1 , i});
}
sort(koll.begin() , koll.end());
int cnt = 0;
for(auto [x , t , i] : koll)
{
if(t == 0)
v[i].first = cnt++;
else
v[i].second = cnt++;
}
// int cnt = 0;
// for(auto p : compress)
// {
// compress[p.first] = cnt++;
// }
fore(i , n)
{
// v[i].first = compress[v[i].first];
// v[i].second = compress[v[i].second];
adj[0][v[i].second] = min(adj[0][v[i].second] , v[i].first);
}
forr(i , 1 , 19)
{
tree[i - 1].init(N , adj[i - 1]);
forr(j , 0 ,N - 1)
{
adj[i][j] = tree[i - 1].query(min(j , adj[i - 1][j]) , j);
}
}
while(q--)
{
int s , e;
cin>>s>>e;
s-- , e--;
if(s == e)
{
cout<<0<<nl;
continue;
}
if(v[s].second > v[e].second)
{
cout<<"impossible"<<nl;
continue;
}
s = v[s].first;
int cur = v[e].second;
e = v[e].second;
int ans = 0;
forn(i , 18 , 0)
{
int ncur = tree[i].query(cur , e);
if(ncur <= s)
continue;
cur = ncur;
ans+=(1<<i);
}
if(ans >= (1<<18))
cout<<"impossible"<<nl;
else
cout<<ans<<nl;
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
62 ms |
109624 KB |
Output is correct |
2 |
Correct |
366 ms |
119160 KB |
Output is correct |
3 |
Correct |
421 ms |
119220 KB |
Output is correct |
4 |
Correct |
480 ms |
119220 KB |
Output is correct |
5 |
Incorrect |
477 ms |
119244 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
57 ms |
109616 KB |
Output is correct |
2 |
Correct |
47 ms |
109620 KB |
Output is correct |
3 |
Correct |
48 ms |
109872 KB |
Output is correct |
4 |
Correct |
46 ms |
109876 KB |
Output is correct |
5 |
Correct |
51 ms |
109872 KB |
Output is correct |
6 |
Incorrect |
64 ms |
109876 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
57 ms |
109616 KB |
Output is correct |
2 |
Correct |
47 ms |
109620 KB |
Output is correct |
3 |
Correct |
48 ms |
109872 KB |
Output is correct |
4 |
Correct |
46 ms |
109876 KB |
Output is correct |
5 |
Correct |
51 ms |
109872 KB |
Output is correct |
6 |
Incorrect |
64 ms |
109876 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
57 ms |
109616 KB |
Output is correct |
2 |
Correct |
47 ms |
109620 KB |
Output is correct |
3 |
Correct |
48 ms |
109872 KB |
Output is correct |
4 |
Correct |
46 ms |
109876 KB |
Output is correct |
5 |
Correct |
51 ms |
109872 KB |
Output is correct |
6 |
Incorrect |
64 ms |
109876 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
367 ms |
118704 KB |
Output is correct |
2 |
Correct |
435 ms |
119952 KB |
Output is correct |
3 |
Correct |
481 ms |
118820 KB |
Output is correct |
4 |
Correct |
331 ms |
119196 KB |
Output is correct |
5 |
Correct |
465 ms |
119472 KB |
Output is correct |
6 |
Correct |
441 ms |
120244 KB |
Output is correct |
7 |
Correct |
441 ms |
119472 KB |
Output is correct |
8 |
Correct |
493 ms |
118988 KB |
Output is correct |
9 |
Correct |
275 ms |
117648 KB |
Output is correct |
10 |
Correct |
402 ms |
119436 KB |
Output is correct |
11 |
Correct |
397 ms |
118700 KB |
Output is correct |
12 |
Correct |
414 ms |
119688 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
62 ms |
109624 KB |
Output is correct |
2 |
Correct |
366 ms |
119160 KB |
Output is correct |
3 |
Correct |
421 ms |
119220 KB |
Output is correct |
4 |
Correct |
480 ms |
119220 KB |
Output is correct |
5 |
Incorrect |
477 ms |
119244 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |