#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
using namespace std;
const int MX = 200005;
struct FenwickTree {
vector<long long> bit; // binary indexed tree
int n = MX;
int sum(int r) {
if(bit.empty()) bit.resize(n);
int ret = 0;
for (; r >= 0; r = (r & (r + 1)) - 1)
ret += bit[r];
return ret;
}
int sum(int l, int r) {
return sum(r) - sum(l - 1);
}
void add(int idx, int delta) {
if(bit.empty()) bit.resize(n);
for (; idx < n; idx = idx | (idx + 1))
bit[idx] += delta;
}
};
const int B = 447;
int N, R, Q;
vector <int> g[MX], region[MX];
int H[MX], st[MX], en[MX], timer=1, stwho[MX];
long long prep[B+10][MX];
void Flat(int v, int p) {
stwho[timer] = v;
st[v] = timer++;
region[H[v]].push_back(st[v]);
for(auto to : g[v]) if(to!=p) {
Flat(to, v);
}
en[v] = timer-1;
}
int main() {
cin >> N >> R >> Q;
cin >> H[1];
for(int i=2; i<=N; ++i) {
int p; cin >> p >> H[i];
g[p].push_back(i);
}
Flat(1, 1);
vector <int> bigs;
int index[R+1], cur=0;
for(int i=1; i<=R; ++i) if(region[i].size()>B) {
bigs.push_back(i);
index[i] = cur++;
}
FenwickTree A;
for(int all=1; all<=R; ++all) {
for(auto it : region[all]) {
A.add(st[it], 1);
}
for(auto b : bigs) {
for(auto it : region[index[b]]) {
prep[index[b]][all] += A.sum(st[it], en[it]);
}
}
for(auto it : region[all]) {
A.add(st[it], -1);
}
}
// O(Q(rootNlogN + logR))
while(Q--) {
int r1, r2;
cin >> r1 >> r2;
long long ans = 0;
if(region[r1].size()>B) {
ans = prep[index[r1]][r2];
} else {
for(auto p1 : region[r1]) {
auto it = upper_bound(region[r2].begin(), region[r2].end(), en[stwho[p1]]);
auto it2 = lower_bound(region[r2].begin(), region[r2].end(), p1);
ans += it-it2;
}
}
assert(ans>=0);
cout << ans << endl;
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
11208 KB |
Output is correct |
2 |
Correct |
8 ms |
11228 KB |
Output is correct |
3 |
Correct |
10 ms |
11208 KB |
Output is correct |
4 |
Correct |
12 ms |
11208 KB |
Output is correct |
5 |
Correct |
16 ms |
11292 KB |
Output is correct |
6 |
Correct |
27 ms |
11348 KB |
Output is correct |
7 |
Correct |
44 ms |
11336 KB |
Output is correct |
8 |
Correct |
32 ms |
11336 KB |
Output is correct |
9 |
Correct |
65 ms |
11720 KB |
Output is correct |
10 |
Correct |
108 ms |
11780 KB |
Output is correct |
11 |
Correct |
152 ms |
12052 KB |
Output is correct |
12 |
Correct |
113 ms |
12488 KB |
Output is correct |
13 |
Correct |
180 ms |
12132 KB |
Output is correct |
14 |
Correct |
314 ms |
12764 KB |
Output is correct |
15 |
Correct |
297 ms |
15252 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1934 ms |
16000 KB |
Output isn't correct |
2 |
Incorrect |
2246 ms |
14660 KB |
Output isn't correct |
3 |
Incorrect |
3383 ms |
17744 KB |
Output isn't correct |
4 |
Correct |
337 ms |
12736 KB |
Output is correct |
5 |
Correct |
363 ms |
14408 KB |
Output is correct |
6 |
Incorrect |
648 ms |
17496 KB |
Output isn't correct |
7 |
Incorrect |
1844 ms |
16164 KB |
Output isn't correct |
8 |
Incorrect |
1533 ms |
28224 KB |
Output isn't correct |
9 |
Correct |
2766 ms |
20032 KB |
Output is correct |
10 |
Incorrect |
4189 ms |
35592 KB |
Output isn't correct |
11 |
Correct |
4746 ms |
19716 KB |
Output is correct |
12 |
Incorrect |
1739 ms |
21516 KB |
Output isn't correct |
13 |
Incorrect |
2270 ms |
21788 KB |
Output isn't correct |
14 |
Incorrect |
2881 ms |
24644 KB |
Output isn't correct |
15 |
Incorrect |
3595 ms |
25784 KB |
Output isn't correct |
16 |
Incorrect |
3375 ms |
31208 KB |
Output isn't correct |
17 |
Incorrect |
3614 ms |
32556 KB |
Output isn't correct |