#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,tune=native")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/hash_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
struct custom_hash {
size_t operator()(uint64_t x) const {
return (x + 228) * 239;
}
};
const int MAX_N = 2e5 + 5;
const int MAX_L = __lg(MAX_N) + 1;
bitset<MAX_N> used_c, used_s;
gp_hash_table<int, int> pos[MAX_N];
set<pair<int, int>> values[MAX_N];
vector<int> graph[MAX_N], parent[MAX_N], dist[MAX_N];
vector<char> deleted[MAX_N];
int ancestors[MAX_N][MAX_L], num[MAX_N] = {}, value[MAX_N], sz[MAX_N];
void find_sizes(int u, int p) {
sz[u] = 1;
for (int v : graph[u]) {
if (v != p && !used_c[v]) {
find_sizes(v, u);
sz[u] += sz[v];
}
}
}
int find_centroid(int u, int p, int n) {
for (int v : graph[u]) {
if (v != p && !used_c[v] && sz[v] > n / 2) {
return find_centroid(v, u, n);
}
}
return u;
}
void DFS(int u, int c, int p, int d) {
pos[c][u] = (int)dist[c].size();
dist[c].push_back(d);
parent[c].push_back(p);
deleted[c].push_back(false);
values[c].insert({value[u], u});
ancestors[u][num[u]++] = c;
for (int v : graph[u]) {
if (v != p && !used_c[v]) {
DFS(v, c, u, d + 1);
}
}
}
void centroid(int u) {
find_sizes(u, -1);
DFS(u, u, -1, 0);
used_c[u] = true;
for (int v : graph[u]) {
if (!used_c[v]) {
centroid(find_centroid(v, u, sz[v]));
}
}
}
void delete_subtree(int u, int p, int c) {
values[c].erase({value[u], u});
deleted[c][pos[c][u]] = true;
for (int v : graph[u]) {
if (v != p && pos[c].find(v) != pos[c].end() && !deleted[c][pos[c][v]]) {
delete_subtree(v, u, c);
}
}
}
int64_t solve(int u) {
used_s[u] = true;
int64_t ans = 0;
for (int i = 0; i < num[u]; i++) {
int A = ancestors[u][i];
if (!deleted[A][pos[A][u]]) {
delete_subtree(u, parent[A][pos[A][u]], A);
}
}
for (int v : graph[u]) {
if (!used_s[v]) {
tuple<int, int, int> val = {-1, -1, -1};
for (int i = 0; i < num[v]; i++) {
int A = ancestors[v][i];
if (!deleted[A][pos[A][v]] && !values[A].empty()) {
auto [valx, x] = *values[A].rbegin();
val = max(val, {valx, -(dist[A][pos[A][x]] + dist[A][pos[A][v]]), x});
}
}
ans = max(ans, solve(get<2>(val)) - get<1>(val) + 1);
}
}
return ans;
}
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
int N;
cin >> N;
for (int i = 0; i < N; i++) {
cin >> value[i];
}
for (int i = 0; i < N - 1; i++) {
int u, v;
cin >> u >> v;
u--, v--;
graph[u].push_back(v);
graph[v].push_back(u);
}
find_sizes(0, -1);
centroid(find_centroid(0, -1, N));
for (int i = 0; i < N; i++) {
if (value[i] == N) {
cout << solve(i) << "\n";
}
}
}
Compilation message
In file included from /usr/include/x86_64-linux-gnu/c++/10/bits/gthr.h:148,
from /usr/include/c++/10/ext/atomicity.h:35,
from /usr/include/c++/10/bits/ios_base.h:39,
from /usr/include/c++/10/ios:42,
from /usr/include/c++/10/istream:38,
from /usr/include/c++/10/sstream:38,
from /usr/include/c++/10/complex:45,
from /usr/include/c++/10/ccomplex:39,
from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
from Main.cpp:3:
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:102:1: error: attribute value 'tune=native' was already specified in 'target' attribute
102 | __gthrw(pthread_once)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:102:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:103:1: error: attribute value 'tune=native' was already specified in 'target' attribute
103 | __gthrw(pthread_getspecific)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:103:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:104:1: error: attribute value 'tune=native' was already specified in 'target' attribute
104 | __gthrw(pthread_setspecific)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:104:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:106:1: error: attribute value 'tune=native' was already specified in 'target' attribute
106 | __gthrw(pthread_create)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:106:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:107:1: error: attribute value 'tune=native' was already specified in 'target' attribute
107 | __gthrw(pthread_join)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:107:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:108:1: error: attribute value 'tune=native' was already specified in 'target' attribute
108 | __gthrw(pthread_equal)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:108:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:109:1: error: attribute value 'tune=native' was already specified in 'target' attribute
109 | __gthrw(pthread_self)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:109:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:110:1: error: attribute value 'tune=native' was already specified in 'target' attribute
110 | __gthrw(pthread_detach)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:110:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:112:1: error: attribute value 'tune=native' was already specified in 'target' attribute
112 | __gthrw(pthread_cancel)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:112:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:114:1: error: attribute value 'tune=native' was already specified in 'target' attribute
114 | __gthrw(sched_yield)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:114:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:116:1: error: attribute value 'tune=native' was already specified in 'target' attribute
116 | __gthrw(pthread_mutex_lock)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:116:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:117:1: error: attribute value 'tune=native' was already specified in 'target' attribute
117 | __gthrw(pthread_mutex_trylock)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:117:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:119:1: error: attribute value 'tune=native' was already specified in 'target' attribute
119 | __gthrw(pthread_mutex_timedlock)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:119:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:121:1: error: attribute value 'tune=native' was already specified in 'target' attribute
121 | __gthrw(pthread_mutex_unlock)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:121:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:122:1: error: attribute value 'tune=native' was already specified in 'target' attribute
122 | __gthrw(pthread_mutex_init)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:122:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:123:1: error: attribute value 'tune=native' was already specified in 'target' attribute
123 | __gthrw(pthread_mutex_destroy)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:123:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:125:1: error: attribute value 'tune=native' was already specified in 'target' attribute
125 | __gthrw(pthread_cond_init)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:125:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:126:1: error: attribute value 'tune=native' was already specified in 'target' attribute
126 | __gthrw(pthread_cond_broadcast)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:126:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:127:1: error: attribute value 'tune=native' was already specified in 'target' attribute
127 | __gthrw(pthread_cond_signal)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:127:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:128:1: error: attribute value 'tune=native' was already specified in 'target' attribute
128 | __gthrw(pthread_cond_wait)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:128:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:129:1: error: attribute value 'tune=native' was already specified in 'target' attribute
129 | __gthrw(pthread_cond_timedwait)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:129:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:130:1: error: attribute value 'tune=native' was already specified in 'target' attribute
130 | __gthrw(pthread_cond_destroy)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:130:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:132:1: error: attribute value 'tune=native' was already specified in 'target' attribute
132 | __gthrw(pthread_key_create)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:132:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:133:1: error: attribute value 'tune=native' was already specified in 'target' attribute
133 | __gthrw(pthread_key_delete)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:133:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:134:1: error: attribute value 'tune=native' was already specified in 'target' attribute
134 | __gthrw(pthread_mutexattr_init)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:134:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:135:1: error: attribute value 'tune=native' was already specified in 'target' attribute
135 | __gthrw(pthread_mutexattr_settype)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:135:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:136:1: error: attribute value 'tune=native' was already specified in 'target' attribute
136 | __gthrw(pthread_mutexattr_destroy)
| ^~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:136:1: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:237:10: error: attribute value 'tune=native' was already specified in 'target' attribute
237 | __gthrw2(__gthrw_(__pthread_key_create),
| ^~~~~~~~
/usr/include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:237:10: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:73:3: error: attribute value 'tune=native' was already specified in 'target' attribute
73 | _GLIBCXX_GTHRW(rwlock_rdlock)
| ^~~~~~~~~~~~~~
/usr/include/c++/10/shared_mutex:73:3: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:74:3: error: attribute value 'tune=native' was already specified in 'target' attribute
74 | _GLIBCXX_GTHRW(rwlock_tryrdlock)
| ^~~~~~~~~~~~~~
/usr/include/c++/10/shared_mutex:74:3: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:75:3: error: attribute value 'tune=native' was already specified in 'target' attribute
75 | _GLIBCXX_GTHRW(rwlock_wrlock)
| ^~~~~~~~~~~~~~
/usr/include/c++/10/shared_mutex:75:3: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:76:3: error: attribute value 'tune=native' was already specified in 'target' attribute
76 | _GLIBCXX_GTHRW(rwlock_trywrlock)
| ^~~~~~~~~~~~~~
/usr/include/c++/10/shared_mutex:76:3: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:77:3: error: attribute value 'tune=native' was already specified in 'target' attribute
77 | _GLIBCXX_GTHRW(rwlock_unlock)
| ^~~~~~~~~~~~~~
/usr/include/c++/10/shared_mutex:77:3: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:91:4: error: attribute value 'tune=native' was already specified in 'target' attribute
91 | __gthrw(pthread_rwlock_timedrdlock);
| ^~~~~~~
/usr/include/c++/10/shared_mutex:91:4: error: attribute value 'tune=native' was already specified in 'target' attribute
/usr/include/c++/10/shared_mutex:101:4: error: attribute value 'tune=native' was already specified in 'target' attribute
101 | __gthrw(pthread_rwlock_timedwrlock);
| ^~~~~~~
/usr/include/c++/10/shared_mutex:101:4: error: attribute value 'tune=native' was already specified in 'target' attribute