#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
const int maxn = 2e5 + 5;
int n, r, q, in[maxn], out[maxn], timer = 0, B = 320, curr = 0, dp[320][25001], i, r1, r2, ans;
short home[maxn], id[maxn];
vector<int> graph[maxn];
vector<pii> by_home[25001];
void dfs(int u) {
in[u] = timer++;
for(int &v : graph[u])
dfs(v);
out[u] = timer;
}
void dfs2(int u, int R, int cnt) {
if(home[u] == R) cnt++;
dp[id[R]][home[u]] += cnt;
for(int &v : graph[u]) dfs2(v, R, cnt);
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
cin >> n >> r >> q;
cin >> home[1];
for(i=2; i<=n; i++) {
int p;
cin >> p >> home[i];
graph[p].push_back(i);
}
dfs(1);
for(i=1; i<=n; i++)
by_home[home[i]].push_back({ in[i], out[i] });
for(i=1; i<=r; i++) {
sort(by_home[i].begin(), by_home[i].end());
if(by_home[i].size() <= B) continue;
id[i] = curr;
dfs2(1, i, 0);
curr++;
}
while(q--) {
cin >> r1 >> r2;
if(by_home[r1].size() > B) {
cout << dp[id[r1]][r2] << endl;
continue;
}
ans = 0;
for(pii &u : by_home[r1]) {
int l=0, r=by_home[r2].size()-1;
int p1 = 1e9, p2 = 1e9;
while(l <= r) {
int mid = (l + r) / 2;
if(by_home[r2][mid].first > u.first) p1 = mid, r = mid - 1;
else l = mid + 1;
}
l=p1, r=by_home[r2].size()-1;
while(l <= r) {
int mid = (l + r) / 2;
if(by_home[r2][mid].first < u.second) p2 = mid, l = mid + 1;
else r = mid - 1;
}
if(p1 != 1e9 && p2 != 1e9) ans += (p2 - p1 + 1);
}
cout << ans << endl;
}
return 0;
}
Compilation message
regions.cpp: In function 'int32_t main()':
regions.cpp:47:30: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
47 | if(by_home[i].size() <= B) continue;
| ~~~~~~~~~~~~~~~~~~^~~~
regions.cpp:56:31: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
56 | if(by_home[r1].size() > B) {
| ~~~~~~~~~~~~~~~~~~~^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
6744 KB |
Output is correct |
2 |
Correct |
2 ms |
6744 KB |
Output is correct |
3 |
Correct |
2 ms |
6744 KB |
Output is correct |
4 |
Correct |
3 ms |
6744 KB |
Output is correct |
5 |
Correct |
6 ms |
6744 KB |
Output is correct |
6 |
Correct |
10 ms |
6744 KB |
Output is correct |
7 |
Correct |
15 ms |
6744 KB |
Output is correct |
8 |
Correct |
18 ms |
6744 KB |
Output is correct |
9 |
Correct |
25 ms |
7172 KB |
Output is correct |
10 |
Correct |
46 ms |
7256 KB |
Output is correct |
11 |
Correct |
62 ms |
7312 KB |
Output is correct |
12 |
Correct |
75 ms |
7804 KB |
Output is correct |
13 |
Correct |
97 ms |
7512 KB |
Output is correct |
14 |
Correct |
163 ms |
8304 KB |
Output is correct |
15 |
Correct |
179 ms |
9952 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1112 ms |
13228 KB |
Output is correct |
2 |
Correct |
1125 ms |
11800 KB |
Output is correct |
3 |
Correct |
1944 ms |
14968 KB |
Output is correct |
4 |
Correct |
161 ms |
8268 KB |
Output is correct |
5 |
Correct |
201 ms |
9416 KB |
Output is correct |
6 |
Correct |
340 ms |
15536 KB |
Output is correct |
7 |
Correct |
703 ms |
14420 KB |
Output is correct |
8 |
Correct |
686 ms |
25392 KB |
Output is correct |
9 |
Correct |
1273 ms |
14988 KB |
Output is correct |
10 |
Correct |
1955 ms |
29960 KB |
Output is correct |
11 |
Correct |
2437 ms |
14704 KB |
Output is correct |
12 |
Correct |
683 ms |
16428 KB |
Output is correct |
13 |
Correct |
1004 ms |
17076 KB |
Output is correct |
14 |
Correct |
1285 ms |
18304 KB |
Output is correct |
15 |
Correct |
2021 ms |
20384 KB |
Output is correct |
16 |
Correct |
2025 ms |
25792 KB |
Output is correct |
17 |
Correct |
1997 ms |
26796 KB |
Output is correct |