#include "bits/stdc++.h"
#ifdef mlocal
#include "./Competitive-Code-Library/snippets/prettyprint.h"
#endif
using namespace std;
#define for_(i, s, e) for (int i = s; i < (int) e; i++)
#define for__(i, s, e) for (ll i = s; i < e; i++)
typedef long long ll;
typedef vector<int> vi;
typedef array<int, 2> ii;
#define endl '\n'
const int INF = 1e9, BS = 300;
int main() {
#ifdef mlocal
freopen("test.in", "r", stdin);
#endif
ios_base::sync_with_stdio(false);
cin.tie(0);
int n; cin >> n;
const int blocks = (n + BS - 1) / BS;
vector<ii> seg(n);
vector<vi> can_reach(n), can_reach_b(blocks);
for_(i, 0, n){
cin >> seg[i][0] >> seg[i][1], seg[i][0]--, seg[i][1]--;
int pt = seg[i][0];
while (pt % BS != 0 and pt <= seg[i][1]) {
can_reach[pt].push_back(i);
pt++;
}
while (pt + BS <= seg[i][1]) {
can_reach_b[pt / BS].push_back(i);
pt += BS;
}
while (pt <= seg[i][1]) {
can_reach[pt].push_back(i);
pt++;
}
}
function<vi(int)> bfs = [&] (int s) {
vi dist(n, INF);
auto cr = can_reach, crb = can_reach_b;
dist[s] = 0;
queue<int> q;
q.push(s);
while (q.size()) {
auto p = q.front(); q.pop();
for (auto i: cr[p]) if (dist[i] == INF) {
dist[i] = dist[p] + 1;
q.push(i);
}
for (auto i: crb[p / BS]) {
if (dist[i] == INF) {
dist[i] = dist[p] + 1;
q.push(i);
}
}
crb[p / BS].clear();
}
return dist;
};
vi ans = bfs(0);
{
vi ans2 = bfs(n - 1);
for_(i, 0, n) ans[i] += ans2[i];
}
for_(i, 1, n - 1) if (ans[i] < INF) ans[i]--;
priority_queue<ii, vector<ii>, greater<ii>> pq;
for_(i, 0, n) pq.push({ans[i], i});
while (pq.size()) {
auto [dist, p] = pq.top(); pq.pop();
if (dist != ans[p]) continue;
for (auto i: can_reach[p]) {
if (ans[i] > ans[p] + 1) {
ans[i] = ans[p] + 1;
pq.push({ans[i], i});
}
}
for (auto i: can_reach_b[p / BS]) {
if (ans[i] > ans[p] + 1) {
ans[i] = ans[p] + 1;
pq.push({ans[i], i});
}
}
can_reach_b[p / BS].clear();
}
int q; cin >> q;
while (q--) {
int p; cin >> p;
p--;
cout << (ans[p] >= INF ? -1 : ans[p]) << endl;
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Execution timed out |
2117 ms |
782388 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
1 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
1 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
344 KB |
Output is correct |
11 |
Correct |
1 ms |
604 KB |
Output is correct |
12 |
Correct |
1 ms |
348 KB |
Output is correct |
13 |
Correct |
1 ms |
860 KB |
Output is correct |
14 |
Correct |
1 ms |
860 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
1 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
1 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
344 KB |
Output is correct |
11 |
Correct |
1 ms |
604 KB |
Output is correct |
12 |
Correct |
1 ms |
348 KB |
Output is correct |
13 |
Correct |
1 ms |
860 KB |
Output is correct |
14 |
Correct |
1 ms |
860 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
6 ms |
4900 KB |
Output is correct |
17 |
Correct |
2 ms |
860 KB |
Output is correct |
18 |
Correct |
8 ms |
7516 KB |
Output is correct |
19 |
Correct |
8 ms |
7516 KB |
Output is correct |
20 |
Correct |
1 ms |
604 KB |
Output is correct |
21 |
Correct |
3 ms |
2180 KB |
Output is correct |
22 |
Correct |
6 ms |
5896 KB |
Output is correct |
23 |
Correct |
4 ms |
3228 KB |
Output is correct |
24 |
Correct |
4 ms |
4188 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
1 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
348 KB |
Output is correct |
8 |
Correct |
1 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
344 KB |
Output is correct |
11 |
Correct |
1 ms |
604 KB |
Output is correct |
12 |
Correct |
1 ms |
348 KB |
Output is correct |
13 |
Correct |
1 ms |
860 KB |
Output is correct |
14 |
Correct |
1 ms |
860 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
6 ms |
4900 KB |
Output is correct |
17 |
Correct |
2 ms |
860 KB |
Output is correct |
18 |
Correct |
8 ms |
7516 KB |
Output is correct |
19 |
Correct |
8 ms |
7516 KB |
Output is correct |
20 |
Correct |
1 ms |
604 KB |
Output is correct |
21 |
Correct |
3 ms |
2180 KB |
Output is correct |
22 |
Correct |
6 ms |
5896 KB |
Output is correct |
23 |
Correct |
4 ms |
3228 KB |
Output is correct |
24 |
Correct |
4 ms |
4188 KB |
Output is correct |
25 |
Correct |
1 ms |
500 KB |
Output is correct |
26 |
Correct |
0 ms |
348 KB |
Output is correct |
27 |
Correct |
7 ms |
5212 KB |
Output is correct |
28 |
Correct |
2 ms |
860 KB |
Output is correct |
29 |
Correct |
2 ms |
604 KB |
Output is correct |
30 |
Correct |
4 ms |
2140 KB |
Output is correct |
31 |
Correct |
4 ms |
2652 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Execution timed out |
2117 ms |
782388 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |