#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int msz = 2e5 + 5;
using pii = pair<int, int>;
vector<int> g[msz];
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n; cin>>n;
vector<int> a(n + 1);
int s = 0;
for (int i = 1; i <= n; i++){
cin>>a[i];
if (a[i] == n){
s = i;
}
}
for (int i = 1; i < n; i++){
int a, b; cin>>a>>b;
g[a].push_back(b);
g[b].push_back(a);
}
vector<bool> used(n + 1);
function<pii(int, int, int)> dfs = [&](int v, int d, int pr){
int maxi = v, dist = d;
for (int i: g[v]){
if (used[i] || i == pr) continue;
auto [mx, dd] = dfs(i, d + 1, v);
if (mx > maxi){
maxi = mx;
dist = dd;
}
}
pii ret = {maxi, dist};
return ret;
};
function<ll(int)> f = [&](int v){
used[v] = true;
ll out = 0;
for (int i: g[v]){
if (used[i]) continue;
auto [u, d] = dfs(i, 1, 0);
out = max(out, d + f(u));
}
return out;
};
cout<<f(s)<<"\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
2 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
4956 KB |
Output is correct |
2 |
Incorrect |
1 ms |
4956 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |