# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1109412 | sano | Regions (IOI09_regions) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<iostream>
#include<vector>
#include<queue>
#include<deque>
#include<string>
#include<fstream>
#include<algorithm>
#include <iomanip>
#include<map>
#include <set>
#include <unordered_map>
#include <stack>
#include <unordered_set>
#include <cmath>
#define ll long long
#define For(i, n) for(ll i = 0; i < (ll)n; i++)
#define ffor(i, a, n) for(ll i = (ll)a; i < (ll)n; i++)
#define rfor(i, n) for(ll i = (ll)n; i >= (ll)0; i--)
#define rffor(i, a, n) for(ll i = (ll)n; i >= (ll)a; i--)
#define vec vector
#define ff first
#define ss second
#define pb push_back
#define shit short double
#define pii pair<ll, ll>
#define NEK 2147483640
#define mod 1000000007
#define mod2 1000000009
#define rsz resize
#define prv1 43
#define prv2 47
#define D 8
using namespace std;
vec<vec<ll>> g;
vec<ll> eul1, eul2;
vec<vec<ll>> odp;
vec<ll> e;
vec<vec<ll>> m;
ll ti = 0;
void DFS(ll x, ll pr) {
eul1[x] = ti; ti++; m[e[x]].push_back(eul1[x]);
for (auto i : g[x]) {
if (i == pr) continue;
DFS(i, x);
}
eul2[x] = ti - 1;
return;
}
bool zorad(vec<ll>& a, vec<ll>& b) {
return a.size() > b.size();
}
void DFS2(ll x, ll pr, ll k, ll v = 0) {
if (e[x] == k) v++;
odp.back()[e[x]] += v;
for (auto i : g[x]) {
if (i == pr) continue;
DFS2(i, x, k, v);
}
return;
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(NULL);
//ifstream cin("promote.in");
//ofstream cout("promote.out");
ll n, r, q;
cin >> n >> r >> q;
vec<vec<ll>> reg(r);
g.resize(n); eul1.resize(n); eul2.resize(n);
e.resize(n);
cin >> e[0]; e[0]--;
reg[e[0]].push_back(0);
ffor(i, 1, n) {
ll x; cin >> x; x--;
g[x].push_back(i);
g[i].push_back(x);
cin >> e[i]; e[i]--;
reg[e[i]].push_back(i);
}
m.resize(r);
DFS(0, -1);
sort(reg.begin(), reg.end(), zorad);
vec<ll> s_n(r);
For(i, reg.size()) {
if (reg[i].size() == 0) s_n[i] = -1;
s_n[e[reg[i][0]]] = i;
}
ll odm = ll(sqrt(n));
vec<ll> trol(r, 0);
For(i, reg.size()) {
if (reg[i].size() >= odm) {
odp.push_back(trol);
DFS2(0, -1, e[reg[i][0]]);
}
}
For(i, m.size()) {
sort(m[i].begin(), m[i].end());
}
For(i, q) {
ll r1, r2; cin >> r1 >> r2; r1--; r2--;
if (s_n[r1] >= odp.size()) {
ll vys = 0;
for (auto i : reg[s_n[r1]]) {
ll q1 = lower_bound(m[r2].begin(), m[r2].end(), eul1[i]) - m[r2].begin();
ll q2 = upper_bound(m[r2].begin(), m[r2].end(), eul2[i]) - m[r2].begin();
vys += q2 - q1;
}
cout << vys << '\n';
}
else {
cout << odp[s_n[r1]][r2] << '\n';
}
}
return 0;
}