#include <bits/stdc++.h>
using namespace std;
const int nax = 2e5 + 5;
int region[nax];
vector<int> edges[nax], positions[nax];
int tin[nax], tout[nax], who[nax];
int timer = 0;
unordered_map<int, int> mp[25005];
void dfs (int u, int p) {
tin[u] = ++timer;
who[timer] = u;
positions[region[u]].push_back(timer);
for (int v : edges[u]) {
if (v != p) {
dfs (v, u);
}
}
tout[u] = timer;
}
void solve() {
int n, r, q;
cin >> n >> r >> q;
cin >> region[1];
for (int i = 2; i <= n; ++i) {
int p;
cin >> p >> region[i];
edges[i].push_back(p);
edges[p].push_back(i);
}
dfs (1, 0);
const int B = sqrt(n);
for (int reg = 1; reg <= r; ++reg) {
if (positions[reg].size() >= B) {
vector<int> pref(n + 2);
for (int i = 1; i <= n; ++i) {
if (region[who[i]] == reg) {
pref[i + 1]++;
pref[tout[who[i]] + 1]--;
}
}
for (int i = 1; i <= n; ++i) {
pref[i] += pref[i - 1];
mp[reg][region[who[i]]] += pref[i];
}
}
}
while (q--) {
int reg1, reg2;
cin >> reg1 >> reg2;
if (positions[reg1].size() >= B) {
cout << mp[reg1][reg2] << endl;
} else {
int ans = 0;
for (int i = 1; i <= n; ++i) {
if (region[who[i]] == reg1) {
auto it1 = upper_bound(positions[reg2].begin(), positions[reg2].end(), tout[who[i]]) - positions[reg2].begin();
auto it2 = lower_bound(positions[reg2].begin(), positions[reg2].end(), i) - positions[reg2].begin();
if (it1 != 0) {
ans += it1 - it2;
}
}
}
cout << ans << endl;
}
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
solve();
}
Compilation message
regions.cpp: In function 'void solve()':
regions.cpp:38:35: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'const int' [-Wsign-compare]
38 | if (positions[reg].size() >= B) {
| ~~~~~~~~~~~~~~~~~~~~~~^~~~
regions.cpp:55:36: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'const int' [-Wsign-compare]
55 | if (positions[reg1].size() >= B) {
| ~~~~~~~~~~~~~~~~~~~~~~~^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
13400 KB |
Output is correct |
2 |
Correct |
3 ms |
13412 KB |
Output is correct |
3 |
Correct |
3 ms |
13400 KB |
Output is correct |
4 |
Correct |
4 ms |
13400 KB |
Output is correct |
5 |
Correct |
7 ms |
13400 KB |
Output is correct |
6 |
Correct |
13 ms |
13400 KB |
Output is correct |
7 |
Correct |
20 ms |
13632 KB |
Output is correct |
8 |
Correct |
25 ms |
13652 KB |
Output is correct |
9 |
Correct |
45 ms |
13912 KB |
Output is correct |
10 |
Correct |
93 ms |
13912 KB |
Output is correct |
11 |
Correct |
166 ms |
14168 KB |
Output is correct |
12 |
Correct |
193 ms |
14424 KB |
Output is correct |
13 |
Correct |
316 ms |
14424 KB |
Output is correct |
14 |
Correct |
410 ms |
14960 KB |
Output is correct |
15 |
Correct |
579 ms |
17148 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3158 ms |
17656 KB |
Output is correct |
2 |
Correct |
3746 ms |
17360 KB |
Output is correct |
3 |
Correct |
6731 ms |
19160 KB |
Output is correct |
4 |
Correct |
597 ms |
14952 KB |
Output is correct |
5 |
Correct |
814 ms |
16152 KB |
Output is correct |
6 |
Correct |
1273 ms |
32372 KB |
Output is correct |
7 |
Correct |
2968 ms |
36676 KB |
Output is correct |
8 |
Correct |
3705 ms |
60696 KB |
Output is correct |
9 |
Execution timed out |
8077 ms |
21020 KB |
Time limit exceeded |
10 |
Runtime error |
407 ms |
131072 KB |
Execution killed with signal 9 |
11 |
Execution timed out |
8092 ms |
22584 KB |
Time limit exceeded |
12 |
Execution timed out |
8041 ms |
23484 KB |
Time limit exceeded |
13 |
Execution timed out |
8002 ms |
24424 KB |
Time limit exceeded |
14 |
Execution timed out |
8007 ms |
38432 KB |
Time limit exceeded |
15 |
Execution timed out |
8093 ms |
28480 KB |
Time limit exceeded |
16 |
Execution timed out |
8010 ms |
33748 KB |
Time limit exceeded |
17 |
Execution timed out |
8057 ms |
46756 KB |
Time limit exceeded |