/*input
6 3 4
1
1 2
1 3
2 3
2 3
5 1
1 2
1 3
2 3
3 1
*/
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
namespace my_template {
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<vl> vll;
typedef vector<pi> vpi;
typedef vector<vpi> vpii;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
typedef vector<pd> vpd;
typedef vector<bool> vb;
typedef vector<vb> vbb;
typedef std::string str;
typedef std::vector<str> vs;
#define x first
#define y second
#define debug(...) cout<<"["<<#__VA_ARGS__<<": "<<__VA_ARGS__<<"]\n"
const ld PI = 3.14159265358979323846264338327950288419716939937510582097494L;
template<typename T>
pair<T, T> operator+(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x + b.x, a.y + b.y); }
template<typename T>
pair<T, T> operator-(const pair<T, T> &a, const pair<T, T> &b) { return pair<T, T>(a.x - b.x, a.y - b.y); }
template<typename T>
T operator*(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.x + a.y * b.y); }
template<typename T>
T operator^(const pair<T, T> &a, const pair<T, T> &b) { return (a.x * b.y - a.y * b.x); }
template<typename T>
void print(vector<T> vec, string name = "") {
cout << name;
for (auto u : vec)
cout << u << ' ';
cout << '\n';
}
}
using namespace my_template;
const int MOD = 1000000007;
const ll INF = std::numeric_limits<ll>::max();
const int MX = 200101;
int N, R, Q;
vi edges[MX];
vi kas;
vii kokie;
vi timeIn;
vi timeOut;
vi atgal;
vi sz;
vi indeks;
vii ats;
vii revAts;
int piv = 0;
int sqr;
int dfs(int x) {
atgal[piv] = x;
timeIn[x] = piv++;
sz[x] = 1;
for (auto u : edges[x])
sz[x] += dfs(u);
timeOut[x] = piv;
return sz[x];
}
void precompute() {
piv = 0;
for (int r = 1; r <= R; ++r)
{
if ((int)kokie[r].size() < sqr) continue;
indeks[r] = piv;
ats.emplace_back(vi(R + 1, 0));
revAts.emplace_back(vi(R + 1, 0));
vi sum(N + 1, 0);
for (int i = 0; i < N; ++i)
sum[i] = (kas[atgal[i]] == r) + (i ? sum[i - 1] : 0);
for (int i = 0; i < N; ++i)
{
int c = atgal[i]; // node
revAts[piv][kas[c]] += sum[timeOut[c] - 1] - (timeIn[c] ? sum[timeIn[c] - 1] : 0);
}
vi plius(N + 1, 0);
for (auto u : kokie[r]) {
plius[u]++;
plius[timeOut[atgal[u]]]--;
}
for (int i = 0; i < N; ++i)
{
plius[i] += (i ? plius[i - 1] : 0);
ats[piv][kas[atgal[i]]] += plius[i];
}
piv++;
}
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> N >> R >> Q;
kas.resize(N + 1);
kokie.resize(R + 1);
timeIn.resize(N + 1);
timeOut.resize(N + 1);
sz.resize(N + 1);
atgal.resize(N + 1);
indeks.resize(N + 1);
sqr = (int)sqrt(N);
cin >> kas[1];
kokie[kas[1]].emplace_back(1);
for (int i = 2; i <= N; ++i)
{
int a; cin >> a >> kas[i];
edges[a].push_back(i);
kokie[kas[i]].emplace_back(i);
}
dfs(1);
for (auto && vec : kokie) {
for (auto && u : vec)
u = timeIn[u];
sort(vec.begin(), vec.end());
}
precompute();
for (int i = 0; i < Q; ++i)
{
int r1, r2;
cin >> r1 >> r2;
int cnt = 0;
if ((int)kokie[r1].size() >= sqr) {
cout << ats[indeks[r1]][r2] << endl;
} else if ((int)kokie[r2].size() >= sqr) {
cout << revAts[indeks[r2]][r1] << endl;
} else {
stack<int> uzdaryt;
int j1 = 0;
int c = 0;
for (auto u : kokie[r2]) {
while (uzdaryt.size() and uzdaryt.top() <= u) {
c--;
uzdaryt.pop();
}
while (j1 < (int)kokie[r1].size() and kokie[r1][j1] <= u) {
uzdaryt.push(timeOut[atgal[ kokie[r1][j1] ]]);
c++;
j1++;
while (uzdaryt.size() and uzdaryt.top() <= u) {
c--;
uzdaryt.pop();
}
}
cnt += c;
}
cout << cnt << endl;
}
}
}
/* Look for:
* special cases (n=1?)
* overflow (ll vs int?)
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* array bounds
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4992 KB |
Output is correct |
2 |
Correct |
3 ms |
4992 KB |
Output is correct |
3 |
Correct |
5 ms |
4992 KB |
Output is correct |
4 |
Correct |
7 ms |
4992 KB |
Output is correct |
5 |
Correct |
10 ms |
5120 KB |
Output is correct |
6 |
Correct |
17 ms |
5120 KB |
Output is correct |
7 |
Correct |
29 ms |
5120 KB |
Output is correct |
8 |
Correct |
35 ms |
5120 KB |
Output is correct |
9 |
Correct |
61 ms |
5504 KB |
Output is correct |
10 |
Correct |
73 ms |
5632 KB |
Output is correct |
11 |
Correct |
87 ms |
5888 KB |
Output is correct |
12 |
Correct |
125 ms |
6400 KB |
Output is correct |
13 |
Correct |
193 ms |
6144 KB |
Output is correct |
14 |
Correct |
201 ms |
7040 KB |
Output is correct |
15 |
Correct |
226 ms |
9216 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
941 ms |
10588 KB |
Output is correct |
2 |
Correct |
1184 ms |
9724 KB |
Output is correct |
3 |
Correct |
1668 ms |
12288 KB |
Output is correct |
4 |
Correct |
255 ms |
6912 KB |
Output is correct |
5 |
Correct |
352 ms |
8440 KB |
Output is correct |
6 |
Correct |
523 ms |
11992 KB |
Output is correct |
7 |
Correct |
833 ms |
13896 KB |
Output is correct |
8 |
Correct |
945 ms |
22392 KB |
Output is correct |
9 |
Correct |
1962 ms |
15160 KB |
Output is correct |
10 |
Correct |
2167 ms |
40312 KB |
Output is correct |
11 |
Correct |
3274 ms |
15648 KB |
Output is correct |
12 |
Correct |
1234 ms |
18728 KB |
Output is correct |
13 |
Correct |
1786 ms |
18728 KB |
Output is correct |
14 |
Correct |
1790 ms |
22016 KB |
Output is correct |
15 |
Correct |
2403 ms |
22360 KB |
Output is correct |
16 |
Correct |
2926 ms |
26200 KB |
Output is correct |
17 |
Correct |
2632 ms |
28520 KB |
Output is correct |