#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
const int maxn = 2e5 + 10;
const int maxr = 25000 + 10;
vector <int> adj[maxn];
int region[maxn];
vector <int> region_members[maxr];
int visit[maxn], finish[maxn];
int n, r, q, t = 0;
void dfs(int s) {
visit[s] = t++;
for (auto i : adj[s])
dfs(i);
finish[s] = t++;
}
vector <vector <int>> r1r2, cnt;
int big_region_cnt = 0;
int big_id[maxn];
void dfs2(int s, int p) {
int id1 = big_id[region[s]];
int id2 = big_id[region[p]];
cnt[s] = cnt[p];
if (id2 != -1 && s != p)
cnt[s][id2]++;
if (id1 != -1) {
for (int i = 0; i < big_region_cnt; i++)
r1r2[i][id1] += cnt[s][i];
}
for (auto i : adj[s])
dfs2(i, s);
}
int main() {
// freopen("in.txt", "r", stdin);
// freopen("out.txt", "w", stdout);
cin >> n >> r >> q;
cin >> region[1];
region_members[region[1]].push_back(1);
for (int i = 2; i <= n; i++) {
int x;
cin >> x;
adj[x].push_back(i);
cin >> region[i];
region_members[region[i]].push_back(i);
}
dfs(1);
vector <vector <int>> starts(r+1);
for (int i = 1; i <= r; i++) {
for (auto j : region_members[i])
starts[i].push_back(visit[j]);
sort(starts[i].begin(), starts[i].end());
}
fill(big_id, big_id + maxn, -1);
for (int i = 1; i <= r; i++) {
if (region_members[i].size() > 500)
big_id[i] = big_region_cnt++;
}
r1r2 = vector <vector <int>> (big_region_cnt + 10, vector <int> (big_region_cnt + 10));
cnt = vector <vector <int>> (n+1, vector <int> (big_region_cnt + 10));
dfs2(1, 1);
while (q--) {
int r1, r2;
cin >> r1 >> r2;
if (region_members[r1].size() <= 500) { // small
int ans = 0;
for (auto i : region_members[r1]) {
auto l = upper_bound(starts[r2].begin(), starts[r2].end(), visit[i]) - starts[r2].begin();
auto r = upper_bound(starts[r2].begin(), starts[r2].end(), finish[i]) - starts[r2].begin();
ans += max(0, (int)(r - l));
}
cout << ans << endl;
} else if (region_members[r2].size() <= 500) { // small
int ans = 0;
for (auto i : region_members[r2]) {
ans += cnt[i][big_id[r1]];
}
cout << ans << endl;
} else {
cout << r1r2[big_id[r1]][big_id[r2]] << endl;
}
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8792 KB |
Output is correct |
2 |
Correct |
2 ms |
8792 KB |
Output is correct |
3 |
Correct |
3 ms |
8792 KB |
Output is correct |
4 |
Correct |
5 ms |
8792 KB |
Output is correct |
5 |
Correct |
5 ms |
8792 KB |
Output is correct |
6 |
Correct |
11 ms |
8792 KB |
Output is correct |
7 |
Correct |
15 ms |
8792 KB |
Output is correct |
8 |
Correct |
17 ms |
9048 KB |
Output is correct |
9 |
Correct |
30 ms |
9816 KB |
Output is correct |
10 |
Correct |
50 ms |
9816 KB |
Output is correct |
11 |
Correct |
80 ms |
10404 KB |
Output is correct |
12 |
Correct |
98 ms |
11460 KB |
Output is correct |
13 |
Correct |
129 ms |
11188 KB |
Output is correct |
14 |
Correct |
218 ms |
12100 KB |
Output is correct |
15 |
Correct |
203 ms |
17024 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1638 ms |
22156 KB |
Output is correct |
2 |
Correct |
1871 ms |
21916 KB |
Output is correct |
3 |
Correct |
2452 ms |
26184 KB |
Output is correct |
4 |
Correct |
202 ms |
12356 KB |
Output is correct |
5 |
Correct |
249 ms |
15508 KB |
Output is correct |
6 |
Correct |
1205 ms |
15212 KB |
Output is correct |
7 |
Correct |
1443 ms |
17332 KB |
Output is correct |
8 |
Correct |
1047 ms |
27096 KB |
Output is correct |
9 |
Correct |
1981 ms |
28264 KB |
Output is correct |
10 |
Correct |
3791 ms |
37952 KB |
Output is correct |
11 |
Correct |
3982 ms |
30496 KB |
Output is correct |
12 |
Correct |
1170 ms |
34120 KB |
Output is correct |
13 |
Correct |
1684 ms |
35048 KB |
Output is correct |
14 |
Correct |
1846 ms |
50816 KB |
Output is correct |
15 |
Correct |
2757 ms |
42496 KB |
Output is correct |
16 |
Correct |
2439 ms |
53572 KB |
Output is correct |
17 |
Correct |
2313 ms |
66764 KB |
Output is correct |