#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5+10;
bool vis[25001];
int n,r,q,cnt=1, a[maxn], st[maxn], en[maxn], B[maxn];
unordered_map<int,int> calc[25001];
vector<int> adj[maxn], v[25001];
void dfs(int s, int p = -1)
{
st[s] = cnt++;
for(auto u : adj[s])
if(u!=p) dfs(u,s);
en[s] = cnt-1;
}
int32_t main()
{
cin >> n >> r >> q >> a[1];
for(int i = 2; i <= n; i++)
{
int x; cin >> x >> a[i];
adj[x].push_back(i);
}
int K = sqrt(n);
dfs(1); for(int i = 1; i <= n; i++) B[st[i]]=i;
for(int i = 1; i <= n; i++) v[a[B[i]]].push_back(st[B[i]]);
for(int i = 1; i <= n; i++)
{
if(vis[a[B[i]]]) continue;
if(v[a[B[i]]].size()<=K) continue;
vis[a[B[i]]]=true;
int pref[n+2]{0};
for(auto u : v[a[B[i]]])
{
int l = st[B[u]], r = en[B[u]];
pref[l]++, pref[r+1]--;
}
for(int j = 1; j <= n; j++)
pref[j]+=pref[j-1], calc[a[B[j]]][a[B[i]]]+=pref[j];
}
while(q--)
{
int a, b, ans = 0; cin >> a >> b;
if(v[a].size()<=K){
for(auto u : v[a]){
int l = st[B[u]], r = en[B[u]];
auto itr = upper_bound(v[b].begin(), v[b].end(), r)-v[b].begin();
auto itr2 = upper_bound(v[b].begin(), v[b].end(), l)-v[b].begin();
if(itr) itr--, ans+=max((int)(itr-itr2)+1, 0);
}
}
else ans = calc[b][a];
cout << ans << endl;
}
}
Compilation message
regions.cpp: In function 'int32_t main()':
regions.cpp:30:29: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
30 | if(v[a[B[i]]].size()<=K) continue;
| ~~~~~~~~~~~~~~~~~^~~
regions.cpp:44:23: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
44 | if(v[a].size()<=K){
| ~~~~~~~~~~~^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8792 KB |
Output is correct |
2 |
Correct |
2 ms |
8792 KB |
Output is correct |
3 |
Correct |
2 ms |
8632 KB |
Output is correct |
4 |
Correct |
5 ms |
8620 KB |
Output is correct |
5 |
Correct |
6 ms |
8792 KB |
Output is correct |
6 |
Correct |
11 ms |
8792 KB |
Output is correct |
7 |
Correct |
15 ms |
9044 KB |
Output is correct |
8 |
Correct |
22 ms |
8792 KB |
Output is correct |
9 |
Correct |
29 ms |
9048 KB |
Output is correct |
10 |
Correct |
45 ms |
9048 KB |
Output is correct |
11 |
Correct |
88 ms |
9304 KB |
Output is correct |
12 |
Correct |
95 ms |
9664 KB |
Output is correct |
13 |
Correct |
131 ms |
9456 KB |
Output is correct |
14 |
Correct |
189 ms |
10064 KB |
Output is correct |
15 |
Correct |
227 ms |
12244 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1516 ms |
12736 KB |
Output is correct |
2 |
Correct |
1670 ms |
11684 KB |
Output is correct |
3 |
Correct |
2389 ms |
14196 KB |
Output is correct |
4 |
Correct |
178 ms |
9788 KB |
Output is correct |
5 |
Correct |
275 ms |
11360 KB |
Output is correct |
6 |
Correct |
476 ms |
29188 KB |
Output is correct |
7 |
Correct |
1004 ms |
32072 KB |
Output is correct |
8 |
Correct |
1198 ms |
57760 KB |
Output is correct |
9 |
Correct |
1797 ms |
16208 KB |
Output is correct |
10 |
Correct |
3423 ms |
118932 KB |
Output is correct |
11 |
Correct |
4099 ms |
15612 KB |
Output is correct |
12 |
Correct |
1168 ms |
20544 KB |
Output is correct |
13 |
Correct |
1587 ms |
20088 KB |
Output is correct |
14 |
Correct |
1775 ms |
33576 KB |
Output is correct |
15 |
Correct |
2714 ms |
25588 KB |
Output is correct |
16 |
Correct |
2369 ms |
31104 KB |
Output is correct |
17 |
Correct |
2644 ms |
42336 KB |
Output is correct |