#include <bits/stdc++.h>
#define all(x) x.begin(), x.end()
using namespace std;
using ll = long long;
using pii = pair<int, int>;
const int MN = 2e5 + 5, MR = 2.5e4 + 5;
int N, R, Q, a[MN], sz[MN], tin[MN], tout[MN], tt;
int lb[MR], sub[MN], cnt1[450][MR], cnt2[MR][450];
vector<int> g[MN];
vector<pii> rg[MR];
void tour(int u) {
tin[u] = ++tt;
for (int v : g[u]) tour(v);
tout[u] = tt;
rg[a[u]].emplace_back(tin[u], tout[u]);
}
void go(int u, int r, int cnt) {
cnt1[lb[r]][a[u]] += cnt;
sub[u] = a[u] == r;
for (int v : g[u]) {
go(v, r, cnt + (a[v] == r));
sub[u] += sub[v];
}
cnt2[a[u]][lb[r]] += sub[u];
}
int solve(int r1, int r2) {
int p1 = 0, p2 = 0, ret = 0;
stack<pii> st;
while (p2 < rg[r2].size()) {
if (p1 == rg[r1].size() || rg[r1][p1].first > rg[r2][p2].first) {
while (!st.empty() && st.top().second < rg[r2][p2].first) st.pop();
p2++;
ret += st.size();
} else if (rg[r1][p1].first < rg[r2][p2].first) {
while (!st.empty() && st.top().second < rg[r1][p1].first) st.pop();
st.push(rg[r1][p1]);
p1++;
}
}
return ret;
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> N >> R >> Q >> a[1];
int B = sqrt(N);
for (int i = 2; i <= N; i++) {
int p; cin >> p >> a[i];
g[p].push_back(i);
sz[a[i]]++;
}
tour(1);
int id = 0;
for (int i = 1; i <= R; i++) {
if (sz[i] >= B) {
lb[i] = ++id;
go(1, i, a[1] == i);
}
sort(all(rg[i]));
}
for (int i = 0; i < Q; i++) {
int r1, r2; cin >> r1 >> r2;
if (sz[r1] >= B) cout << cnt1[lb[r1]][r2] << endl;
else if (sz[r2] >= B) cout << cnt2[r1][lb[r2]] << endl;
else cout << solve(r1, r2) << endl;
}
return 0;
}
Compilation message
regions.cpp: In function 'int solve(int, int)':
regions.cpp:32:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
32 | while (p2 < rg[r2].size()) {
| ~~~^~~~~~~~~~~~~~~
regions.cpp:33:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
33 | if (p1 == rg[r1].size() || rg[r1][p1].first > rg[r2][p2].first) {
| ~~~^~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
5612 KB |
Output is correct |
2 |
Correct |
4 ms |
5740 KB |
Output is correct |
3 |
Correct |
6 ms |
5612 KB |
Output is correct |
4 |
Correct |
10 ms |
5632 KB |
Output is correct |
5 |
Correct |
11 ms |
5740 KB |
Output is correct |
6 |
Correct |
18 ms |
5740 KB |
Output is correct |
7 |
Correct |
34 ms |
5740 KB |
Output is correct |
8 |
Correct |
49 ms |
5740 KB |
Output is correct |
9 |
Correct |
31 ms |
5996 KB |
Output is correct |
10 |
Correct |
86 ms |
6124 KB |
Output is correct |
11 |
Correct |
143 ms |
6508 KB |
Output is correct |
12 |
Correct |
171 ms |
7020 KB |
Output is correct |
13 |
Correct |
137 ms |
6636 KB |
Output is correct |
14 |
Correct |
242 ms |
7916 KB |
Output is correct |
15 |
Correct |
270 ms |
12368 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1122 ms |
11860 KB |
Output is correct |
2 |
Correct |
1223 ms |
10104 KB |
Output is correct |
3 |
Correct |
2228 ms |
14700 KB |
Output is correct |
4 |
Correct |
220 ms |
7276 KB |
Output is correct |
5 |
Correct |
355 ms |
8940 KB |
Output is correct |
6 |
Correct |
770 ms |
23168 KB |
Output is correct |
7 |
Correct |
1024 ms |
30060 KB |
Output is correct |
8 |
Correct |
1224 ms |
39940 KB |
Output is correct |
9 |
Correct |
1772 ms |
14940 KB |
Output is correct |
10 |
Correct |
2929 ms |
78104 KB |
Output is correct |
11 |
Correct |
2722 ms |
14532 KB |
Output is correct |
12 |
Correct |
1235 ms |
45292 KB |
Output is correct |
13 |
Correct |
1811 ms |
46044 KB |
Output is correct |
14 |
Correct |
2503 ms |
53744 KB |
Output is correct |
15 |
Correct |
2570 ms |
68324 KB |
Output is correct |
16 |
Correct |
2333 ms |
79332 KB |
Output is correct |
17 |
Correct |
2457 ms |
69752 KB |
Output is correct |