#include<bits/stdc++.h>
#include<fstream>
using namespace std;
#define sz(a) (int)a.size()
#define ALL(v) v.begin(), v.end()
#define ALLR(v) v.rbegin(), v.rend()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mpp make_pair
const ld PI = 3.14159265359, prec = 1e-9;;
//using u128 = __uint128_t;
//const int x[4] = {1, 0, -1, 0};
//const int y[4] = {0, -1, 0, 1};
const ll mod = 1e9 + 7, pr = 31;
const int mxn = 1e5 + 5, mxq = 1e5 + 5, sq = 500, mxv = 5e4 + 1;
//const int base = (1 <<18);
const ll inf = 1e9 + 5, neg = -69420, inf2 = 1e14;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// have fun!
int n;
int siz[mxn + 1], pa[mxn + 1], dep[mxn + 1], head[mxn + 1], c[mxn + 1];
deque<pair<int, int>>dq[mxn + 1];
vt<int>adj[mxn + 1];
int bit[mxn + 1];
vt<pii>comp;
void upd(int p, int v, bool add = 1){
if(add)comp.pb(mpp(p, v));
while(p <= n){
bit[p] += v; p += p & (-p);
}
}
ll get(int p){
ll ans = 0;
while(p){
ans += bit[p]; p -= p & (-p);
}
return(ans);
}
void reset(){
for(auto [node, val]: comp){
upd(node, -val, 0);
}
comp.clear();
}
void dfs(int s, int pre){
siz[s] = 1; pa[s] = pre;
for(auto i: adj[s]){
if(i != pre){
dep[i] = dep[s] + 1;
dfs(i, s); siz[s] += siz[i];
}
}
}
void hld(int s, int pre, int group){
dq[group].pb(mpp(c[s], 1)); head[s] = group;
int mx = 0, son = 0;
for(auto i: adj[s]){
if(i != pre){
if(siz[i] > mx){
mx = siz[i]; son = i;
}
}
}
if(!mx)return;
hld(son, s, group);
for(auto i: adj[s]){
if(i != pre && i != son){
hld(i, s, i);
}
}
}
void solve(){
cin >> n;
vt<int>cc;
for(int i = 1; i <= n; i++){
cin >> c[i]; cc.pb(c[i]);
}
sort(ALL(cc));
for(int i = 1; i <= n; i++){
c[i] = lower_bound(ALL(cc), c[i]) - cc.begin() + 1;
}
vt<pii>edge;
for(int i = 1; i < n; i++){
int u, v; cin >> u >> v;
adj[u].pb(v); adj[v].pb(u);
edge.pb(mpp(u, v));
}
dfs(1, -1);
hld(1, -1, 1);
for(int i = 0; i < n - 1; i++){
int a = edge[i].fi, b = edge[i].se;
int dif = dep[a] - dep[head[a]] + 1;
vt<pii>query;
while(dif && sz(dq[head[a]])){
if(dif >= dq[head[a]].front().se){
dif -= dq[head[a]].front().se;
query.pb(dq[head[a]].front()); dq[head[a]].pop_front();
}else{
dq[head[a]].front().se -= dif;
query.pb(mpp(dq[head[a]].front().fi, dif));
dif = 0;
}
}
dq[head[a]].push_front(mpp(c[b], dep[a] - dep[head[a]] + 1));
reverse(ALL(query));
a = pa[head[a]];
if(a != -1){
while(head[a] != 1){
for(int j = sz(dq[head[a]]) - 1; j >= 0; j--){
query.pb(dq[head[a]][j]);
}
dq[head[a]].clear();
dq[head[a]].pb(mpp(c[b], dep[a] - dep[head[a]] + 1));
a = pa[head[a]];
}
int dif = dep[a] + 1;
//for(auto j: dq[head[1]])cout << j.fi << " " << j.se << "\n";
vt<pii>back;
while(dif && sz(dq[head[a]])){
if(dif >= dq[head[a]].front().se){
dif -= dq[head[a]].front().se;
back.pb(dq[head[a]].front()); dq[head[a]].pop_front();
}else{
dq[head[a]].front().se -= dif;
back.pb(mpp(dq[head[a]].front().fi, dif));
dif = 0;
}
}
dq[head[a]].push_front(mpp(c[b], dep[a] + 1));
reverse(ALL(back));
for(auto j: back)query.pb(j);
}
ll res = 0;
for(auto [val, cnt]: query){
//cout << val << " " << cnt << "\n";
//assert(val > 0);
res += get(val - 1) * cnt; upd(val, cnt);
}
reset();
cout << res << "\n";
}
}
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//freopen("DATA.inp", "r", stdin);
//freopen("DATA.out", "w", stdout);
int tt; tt = 1;
while(tt--){
solve();
}
return(0);
}
Compilation message
construction.cpp: In function 'void reset()':
construction.cpp:50:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
50 | for(auto [node, val]: comp){
| ^
construction.cpp: In function 'void solve()':
construction.cpp:160:17: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
160 | for(auto [val, cnt]: query){
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
36 ms |
72020 KB |
Output is correct |
| 2 |
Correct |
35 ms |
72248 KB |
Output is correct |
| 3 |
Incorrect |
35 ms |
72016 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
36 ms |
72020 KB |
Output is correct |
| 2 |
Correct |
35 ms |
72248 KB |
Output is correct |
| 3 |
Incorrect |
35 ms |
72016 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
36 ms |
72020 KB |
Output is correct |
| 2 |
Correct |
35 ms |
72248 KB |
Output is correct |
| 3 |
Incorrect |
35 ms |
72016 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
