#pragma GCC target ("avx2")
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include<bits/stdc++.h>
#include<math.h>
using namespace std;
typedef int ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef vector<ll> vl;
#define FD(i, r, l) for(ll i = r; i > (l); --i)
#define K first
#define V second
#define G(x) ll x; cin >> x;
#define GD(x) ld x; cin >> x;
#define GS(s) string s; cin >> s;
#define EX(x) { cout << x << '\n'; exit(0); }
#define A(a) (a).begin(), (a).end()
#define F(i, l, r) for (ll i = l; i < (r); ++i)
template<typename A, typename B>
A& chmax(A &a, B b) { return a < b ? (a=b): a; }
template<typename A, typename B>
A& chmin(A &a, B b) { return a > b ? (a=b): a; }
const ll NN = 2e5 + 1;
const ll HEAVYTH = 550;
// const ll HEAVYTH = 750;
const ll RR = 2.5e4 + 1;
const ll AMT = RR / HEAVYTH + 6;
ll label[NN], tin[NN], tout[NN];
vl people[RR];
vl adj[NN];
vl dfsorder;
vl heavies;
ll sz[NN];
void dfsinit(ll i) {
static int time = 0;
tin[i] = time++;
dfsorder.push_back(i);
sort(A(adj[i]), [&](ll a, ll b) {
return sz[a] > sz[b];
});
for (auto x: adj[i]) dfsinit(x);
tout[i] = time;
}
bool isPar(ll i, ll j) {
return tin[i] <= tin[j] and tin[j] < tout[i];
}
ll heavyRoot[AMT][RR];
void solveHeavyRoot(ll ask, ll put) {
// compute number of ask labels on path to root, add to ans
vl stk;
ll cnt = 0;
for (auto x: dfsorder) {
while (stk.size() and !isPar(stk.back(), x)) {
cnt -= label[stk.back()] == ask;
stk.pop_back();
}
cnt += label[x] == ask;
stk.push_back(x);
heavyRoot[put][label[x]] += cnt;
}
}
ll containsHeavy[AMT][RR];
void solveContainsHeavy(ll ask, ll put) {
// compute number of ask in subtree, then add to answer
vl ans(dfsorder.size() + 1);
FD(i, ll(dfsorder.size()) - 1, -1) {
ll x = dfsorder[i];
for (auto y: adj[x]) ans[x] += ans[y];
ans[x] += label[x] == ask;
containsHeavy[put][label[x]] += ans[x];
}
}
vl peopleWhenQuerying[RR];
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
G(n) G(r) G(q)
cin >> label[1]; people[label[1]].push_back(1);
vl p(n+1);
F(i, 2, n+1) {
G(par) cin >> label[i];
adj[par].push_back(i);
people[label[i]].push_back(i);
p[i] = par;
}
FD(i, n, 1) sz[p[i]]+= ++sz[i];
dfsinit(1);
F(i, 1, r+1) if (people[i].size() >= HEAVYTH) {
heavies.push_back(i);
}
F(i, 0, heavies.size()) {
solveHeavyRoot(heavies[i], i);
}
F(i, 0, heavies.size()) {
solveContainsHeavy(heavies[i], i);
}
F(i, 1, r+1) if (people[i].size() < HEAVYTH) {
peopleWhenQuerying[i] = people[i];
for (auto &x: peopleWhenQuerying[i]) x = tin[x];
sort(A(peopleWhenQuerying[i]));
}
// cout << heavies.size() << " vs " << r << endl;
// exit(0);
while (q--) {
G(r1) G(r2)
if (people[r1].size() >= HEAVYTH) {
cout << heavyRoot[lower_bound(A(heavies), r1) - heavies.begin()][r2] << endl;
} else if (people[r2].size() >= HEAVYTH) {
cout << containsHeavy[lower_bound(A(heavies), r2) - heavies.begin()][r1] << endl;
} else {
ll ans = 0;
for (auto x: people[r1]) {
ans += lower_bound(A(peopleWhenQuerying[r2]), tout[x]) - lower_bound(A(peopleWhenQuerying[r2]), tin[x]);
}
cout << ans << endl;
}
}
}
Compilation message
regions.cpp: In function 'int main()':
regions.cpp:22:37: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
22 | #define F(i, l, r) for (ll i = l; i < (r); ++i)
| ^
regions.cpp:126:5: note: in expansion of macro 'F'
126 | F(i, 0, heavies.size()) {
| ^
regions.cpp:22:37: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
22 | #define F(i, l, r) for (ll i = l; i < (r); ++i)
| ^
regions.cpp:130:5: note: in expansion of macro 'F'
130 | F(i, 0, heavies.size()) {
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
10840 KB |
Output is correct |
| 2 |
Correct |
2 ms |
10840 KB |
Output is correct |
| 3 |
Correct |
4 ms |
10840 KB |
Output is correct |
| 4 |
Correct |
4 ms |
10840 KB |
Output is correct |
| 5 |
Correct |
5 ms |
10840 KB |
Output is correct |
| 6 |
Correct |
11 ms |
10840 KB |
Output is correct |
| 7 |
Correct |
16 ms |
10840 KB |
Output is correct |
| 8 |
Correct |
23 ms |
10840 KB |
Output is correct |
| 9 |
Correct |
29 ms |
11352 KB |
Output is correct |
| 10 |
Correct |
40 ms |
11384 KB |
Output is correct |
| 11 |
Correct |
70 ms |
11608 KB |
Output is correct |
| 12 |
Correct |
91 ms |
12120 KB |
Output is correct |
| 13 |
Correct |
107 ms |
11744 KB |
Output is correct |
| 14 |
Correct |
198 ms |
12120 KB |
Output is correct |
| 15 |
Correct |
193 ms |
15316 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
955 ms |
19684 KB |
Output is correct |
| 2 |
Correct |
968 ms |
18068 KB |
Output is correct |
| 3 |
Correct |
1747 ms |
21648 KB |
Output is correct |
| 4 |
Correct |
209 ms |
12376 KB |
Output is correct |
| 5 |
Correct |
214 ms |
14340 KB |
Output is correct |
| 6 |
Correct |
1097 ms |
13632 KB |
Output is correct |
| 7 |
Correct |
1253 ms |
14552 KB |
Output is correct |
| 8 |
Correct |
923 ms |
20340 KB |
Output is correct |
| 9 |
Correct |
1663 ms |
19784 KB |
Output is correct |
| 10 |
Correct |
3478 ms |
25952 KB |
Output is correct |
| 11 |
Correct |
3420 ms |
19616 KB |
Output is correct |
| 12 |
Correct |
854 ms |
22872 KB |
Output is correct |
| 13 |
Correct |
1237 ms |
23200 KB |
Output is correct |
| 14 |
Correct |
1416 ms |
26880 KB |
Output is correct |
| 15 |
Correct |
2211 ms |
28216 KB |
Output is correct |
| 16 |
Correct |
2175 ms |
36056 KB |
Output is correct |
| 17 |
Correct |
1937 ms |
38024 KB |
Output is correct |
