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;
const int maxn = 2e5 + 5;
const int maxr = 25005;
const int blsz = 500;
int n, r, q;
int bigans[blsz][maxr];
int cnt[maxr], bigid[maxr], H[maxn];
int bigcnt = 0, tdfs = 0;
vector<int> g[maxn];
vector<pair<int, int>> euler[maxr];
void dfs(int x){
tdfs++;
euler[H[x]].push_back({tdfs, 1});
cnt[H[x]]++;
for(auto v: g[x])dfs(v);
tdfs++;
euler[H[x]].push_back({tdfs, -1});
}
void dfs_calc(int x, int id, int dep){
if(H[x] == id)dep++;
else bigans[bigcnt][H[x]] += dep;
for(auto v: g[x])dfs_calc(v, id, dep);
}
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);
}
dfs(1);
for(int i = 1; i <= r; i++){
if(cnt[i] >= blsz){
bigcnt++;
assert(bigcnt < blsz);
bigid[i] = bigcnt;
dfs_calc(1, i, 0);
}
}
while(q--){
int r1, r2;
cin >> r1 >> r2;
if(cnt[r1] >= blsz)cout << bigans[bigid[r1]][r2] << endl;
else {
int ptr1 = 0, ptr2 = 0, dep = 0, ans = 0;
while(ptr1 < euler[r1].size() && ptr2 < euler[r2].size()){
if(euler[r1][ptr1].first < euler[r2][ptr2].first){
dep += euler[r1][ptr1++].second;
}
else {
if(euler[r2][ptr2++].second == 1)ans += dep;
}
}
cout << ans << endl;
}
}
}
Compilation message (stderr)
regions.cpp: In function 'int main()':
regions.cpp:56:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
56 | while(ptr1 < euler[r1].size() && ptr2 < euler[r2].size()){
| ~~~~~^~~~~~~~~~~~~~~~~~
regions.cpp:56:51: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
56 | while(ptr1 < euler[r1].size() && ptr2 < euler[r2].size()){
| ~~~~~^~~~~~~~~~~~~~~~~~
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |