#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
struct DSUF{
vector<ll> P;
ll fs(ll node){
if(P[node]==node) return node;
return P[node]=fs(P[node]);
}
void us(ll a, ll b){
a=fs(a);b=fs(b);
if(a!=b) P[b]=a;
}
DSUF(ll n){
P.assign(n+5,0);
for(int i=0; i<P.size(); i++)
P[i]=i;
}
};
vector<ll> g[200001], v(200001,0),G[200001];
ll bl[22][200001];
void dfs(ll node)
{
for(int j=1; j<22; j++)
bl[j][node]=bl[j-1][bl[j-1][node]];
for(auto i:G[node])
if(v[i]==0){
v[i]=v[node]+1;
bl[0][i]=node;
dfs(i);
}
}
ll cost(ll a, ll b)
{
if(v[a]<v[b])
swap(a,b);
ll cost=v[a]-v[b];
for(int i=21; i>-1; i--)
if((cost&(1<<i))!=0)
a=bl[i][a];
for(int i=21; i>-1; i--)
{
if(bl[i][a]!=bl[i][b])
{
a=bl[i][a];
b=bl[i][b];
cost+=(1<<i)*2;
}
}
if(a!=b) cost+=2;
return cost;
}
int main()
{
ll n;
cin>>n;
pair<ll,ll> cad[n];
DSUF asd(n+2);
for(int i=0; i<n; i++)
{
cin>>cad[i].first;
cad[i].second=i+1;
}
for(int i=0; i<n-1; i++)
{
ll a,b;
cin>>a>>b;
a = cad[a-1].first;
b = cad[b-1].first;
if(a < b) swap(a,b);
g[a].push_back(b);
G[a].push_back(b);
G[b].push_back(a);
}
dfs(1);
sort(cad,cad+n);
ll sol[n+2]={ };
for(int i=0; i<n; i++)
{
pair<ll,ll> temp=cad[i];
for(auto i:g[temp.second])
{
sol[temp.second]=max(sol[temp.second],sol[asd.fs(i)]+cost(temp.second,asd.fs(i)));
asd.us(temp.second,i);
}
}
cout<<sol[cad[n-1].second];
}
Compilation message
Main.cpp: In constructor 'DSUF::DSUF(ll)':
Main.cpp:16:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
16 | for(int i=0; i<P.size(); i++)
| ~^~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
11 ms |
45660 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
45620 KB |
Output is correct |
2 |
Correct |
7 ms |
45660 KB |
Output is correct |
3 |
Incorrect |
9 ms |
45616 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |