#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
const int maxn = 1e5 + 5;
int n, r, q, home[maxn], timer = 0, curr = 1, i, r1, r2, ans, L, R, p1, p2, mid;
vector<vector<int> > graph;
vector<vector<pii> > by_home;
int in[maxn], out[maxn], dp[330][25001], id[maxn];
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;
int B = static_cast<int>(sqrt(n));
graph.resize(n+1);
by_home.resize(r+1);
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) {
ans = 0;
for(pii &u : by_home[r1]) {
L=0, R=by_home[r2].size()-1, p1 = 1e9, p2 = 1e9;
while(L <= R) {
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) {
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;
} else {
cout << dp[id[r1]][r2] << endl;
}
}
return 0;
}
Compilation message
regions.cpp: In function 'int32_t main()':
regions.cpp:49:30: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
49 | if(by_home[i].size() <= B) continue;
| ~~~~~~~~~~~~~~~~~~^~~~
regions.cpp:58:31: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
58 | if(by_home[r1].size() <= B) {
| ~~~~~~~~~~~~~~~~~~~^~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
2392 KB |
Output is correct |
3 |
Correct |
1 ms |
2804 KB |
Output is correct |
4 |
Correct |
3 ms |
2392 KB |
Output is correct |
5 |
Correct |
4 ms |
2392 KB |
Output is correct |
6 |
Correct |
8 ms |
2392 KB |
Output is correct |
7 |
Correct |
14 ms |
2392 KB |
Output is correct |
8 |
Correct |
15 ms |
2648 KB |
Output is correct |
9 |
Correct |
21 ms |
2904 KB |
Output is correct |
10 |
Correct |
38 ms |
3160 KB |
Output is correct |
11 |
Correct |
60 ms |
3416 KB |
Output is correct |
12 |
Correct |
73 ms |
4156 KB |
Output is correct |
13 |
Correct |
83 ms |
3928 KB |
Output is correct |
14 |
Correct |
125 ms |
6816 KB |
Output is correct |
15 |
Correct |
185 ms |
9528 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1135 ms |
12764 KB |
Output is correct |
2 |
Correct |
1099 ms |
9644 KB |
Output is correct |
3 |
Correct |
1853 ms |
12852 KB |
Output is correct |
4 |
Correct |
154 ms |
4792 KB |
Output is correct |
5 |
Correct |
205 ms |
6080 KB |
Output is correct |
6 |
Correct |
342 ms |
12696 KB |
Output is correct |
7 |
Correct |
697 ms |
14136 KB |
Output is correct |
8 |
Correct |
733 ms |
24232 KB |
Output is correct |
9 |
Execution timed out |
8042 ms |
10740 KB |
Time limit exceeded |
10 |
Runtime error |
35 ms |
25400 KB |
Execution killed with signal 11 |
11 |
Runtime error |
32 ms |
20956 KB |
Execution killed with signal 11 |
12 |
Incorrect |
28 ms |
13456 KB |
Unexpected end of file - int32 expected |
13 |
Runtime error |
40 ms |
27248 KB |
Execution killed with signal 11 |
14 |
Execution timed out |
8032 ms |
13432 KB |
Time limit exceeded |
15 |
Runtime error |
34 ms |
26228 KB |
Execution killed with signal 11 |
16 |
Runtime error |
36 ms |
29560 KB |
Execution killed with signal 11 |
17 |
Incorrect |
31 ms |
17376 KB |
Unexpected end of file - int32 expected |