#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = LLONG_MAX / 2 - INT_MAX;
const int maxn = 200005;
const int maxr = 25005;
const int sqrtn = 450;
const int sqrtr = 160;
int n, r, q;
vector<int> adj[maxn];
int re[maxn];
int cnt = 0;
vector<int> sts[maxr], ens[maxr];
int s[maxr], prec[sqrtr][maxr], prec2[maxr][sqrtr], cnt2 = 0;
void dfs(int nd, int par) {
sts[re[nd]].push_back(cnt++);
for (auto i : adj[nd])
if (i != par)
dfs(i, nd);
ens[re[nd]].push_back(cnt);
}
int curreg;
int dfs2(int nd, int par, int num) {
if (re[nd] != curreg) prec[s[curreg]][re[nd]] += num;
num += re[nd] == curreg;
int num_current = re[nd] == curreg;
for (auto i : adj[nd])
if (i != par)
num_current += dfs2(i, nd, num);
if (re[nd] != curreg) prec2[re[nd]][s[curreg]] += num_current;
return num_current;
}
int qry(int a, int b) {
int cnt = 0, num = 0;
int c1 = 0, c2 = 0, c3 = 0;
while (c2 < sts[b].size() && c3 < ens[a].size()) {
int nxt = min(min((c1 < sts[a].size() ? sts[a][c1] : INF), sts[b][c2]), ens[a][c3]);
if (ens[a][c3] == nxt) { cnt--; c3++; continue; }
if (c1 < sts[a].size() && sts[a][c1] == nxt) { cnt++; c1++; continue; }
if (sts[b][c2] == nxt) { num += cnt; c2++; continue; }
}
return num;
}
signed main() {
cin.tie(nullptr) -> ios::sync_with_stdio(false);
fill(s, s+maxr, -1);
cin >> n >> r >> q;
cin >> re[0]; re[0]--;
for (int i = 1; i < n; i++)
{ int a; cin >> a >> re[i]; a--, re[i]--; adj[a].push_back(i); }
dfs(0, 0);
for (int i = 0; i < r; i++)
if (sts[i].size() >= sqrtn) {
s[i] = cnt2++; curreg = i;
dfs2(0, 0, 0);
}
for (int i = 0; i < q; i++) {
int a, b; cin >> a >> b; a--, b--;
if (s[a] != -1) {cout << prec[s[a]][b] << endl; continue;}
if (s[b] != -1) {cout << prec2[a][s[b]] << endl; continue;}
cout << qry(a, b) << endl;
}
}
Compilation message
regions.cpp: In function 'long long int qry(long long int, long long int)':
regions.cpp:49:15: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
49 | while (c2 < sts[b].size() && c3 < ens[a].size()) {
| ~~~^~~~~~~~~~~~~~~
regions.cpp:49:37: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
49 | while (c2 < sts[b].size() && c3 < ens[a].size()) {
| ~~~^~~~~~~~~~~~~~~
regions.cpp:50:31: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
50 | int nxt = min(min((c1 < sts[a].size() ? sts[a][c1] : INF), sts[b][c2]), ens[a][c3]);
| ~~~^~~~~~~~~~~~~~~
regions.cpp:52:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
52 | if (c1 < sts[a].size() && sts[a][c1] == nxt) { cnt++; c1++; continue; }
| ~~~^~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 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 |
4 ms |
8792 KB |
Output is correct |
| 5 |
Correct |
5 ms |
8792 KB |
Output is correct |
| 6 |
Correct |
14 ms |
9048 KB |
Output is correct |
| 7 |
Correct |
21 ms |
9048 KB |
Output is correct |
| 8 |
Correct |
25 ms |
9048 KB |
Output is correct |
| 9 |
Correct |
29 ms |
9560 KB |
Output is correct |
| 10 |
Correct |
44 ms |
9420 KB |
Output is correct |
| 11 |
Correct |
79 ms |
9816 KB |
Output is correct |
| 12 |
Correct |
95 ms |
10328 KB |
Output is correct |
| 13 |
Correct |
93 ms |
10124 KB |
Output is correct |
| 14 |
Correct |
153 ms |
10764 KB |
Output is correct |
| 15 |
Correct |
155 ms |
13852 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
717 ms |
20128 KB |
Output is correct |
| 2 |
Correct |
754 ms |
18968 KB |
Output is correct |
| 3 |
Correct |
1216 ms |
22204 KB |
Output is correct |
| 4 |
Correct |
198 ms |
10748 KB |
Output is correct |
| 5 |
Correct |
216 ms |
12616 KB |
Output is correct |
| 6 |
Correct |
446 ms |
34660 KB |
Output is correct |
| 7 |
Correct |
810 ms |
31500 KB |
Output is correct |
| 8 |
Correct |
775 ms |
53980 KB |
Output is correct |
| 9 |
Correct |
1239 ms |
18932 KB |
Output is correct |
| 10 |
Correct |
1522 ms |
67472 KB |
Output is correct |
| 11 |
Correct |
1792 ms |
18532 KB |
Output is correct |
| 12 |
Correct |
648 ms |
42000 KB |
Output is correct |
| 13 |
Correct |
911 ms |
42720 KB |
Output is correct |
| 14 |
Correct |
1206 ms |
52612 KB |
Output is correct |
| 15 |
Correct |
1465 ms |
57184 KB |
Output is correct |
| 16 |
Correct |
1492 ms |
64280 KB |
Output is correct |
| 17 |
Correct |
1461 ms |
63440 KB |
Output is correct |
