| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 731677 | Desh03 | 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 <bits/stdc++.h>
using namespace std;
vector<int> r[25000], g[200000], euler;
int in[200000], out[200000], fr[25000], ans[25000][25000];
short int c[200000];
int t;
const short int block = 447;
void dfs(int u) {
in[u] = t++;
euler.push_back(c[u]);
for (int v : g[u])
dfs(v);
out[u] = t - 1;
}
void add(int x) {
fr[euler[x]]++;
}
void remove(int x) {
fr[euler[x]]--;
}
int main() {
int n, rr, qq;
cin >> n >> rr >> qq;
int x, h;
cin >> h;
h--;
r[h].push_back(0);
c[0] = h;
for (int i = 1; i < n; i++) {
cin >> x >> h;
x--, h--;
r[h].push_back(i);
g[x].push_back(i);
c[i] = h;
}
dfs(0);
for (int i = 0; i < rr; i++) {
sort(r[i].begin(), r[i].end(), [](const int &a, const int &b) {
int a1 = in[a] / block, b1 = in[b] / block;
return a1 == b1 ? out[a] < out[b] : a1 < b1;
});
}
for (int i = 0; i < rr; i++) {
int lb, rb;
if (r[i].size()) lb = in[r[i][0]] + 1, rb = lb - 1;
for (int u : r[i]) {
int l_ = in[u] + 1, r_ = out[u];
while (lb > l_) add(--lb);
while (rb < r_) add(++rb);
while (lb < l_) remove(lb++);
while (rb > r_) remove(rb--);
for (int j = 0; j < rr; j++)
if (fr[j]) ans[i][j] += fr[j];
}
if (r[i].size()) for (int j = 0; j < rr; j++) fr[j] = 0;
}
while (qq--) {
int a, b;
cin >> a >> b;
cout << ans[--a][--b] << endl;
}
}