r2Sq2z - Online C++0x Compiler & Debugging Tool

#include<bits/stdc++.h>
#define TIME (1.0* clock()/CLOCKS_PER_SEC)
#define pb push_back
#define eb emplace_back
#define id1 (id<<1)
#define id2 (id<<1)|1
#define ll long long
#define ii pair<int,int>
#define vi vector<int>
#define vii vector<pair<int,int>>
#define vl vector<long long>
#define vll vector <pair<ll,ll>>
#define li pair<long long,int>
#define vil vector <pair<int,ll>>
#define db double
#define ff first
#define ss second
#define lb lower_bound
#define ub upper_bound
#define FOR(i, a, b) for (int i = (a); i <=(b); i++)
#define F0R(i, a) FOR(i, 0, a-1)
#define ROF(i, a, b) for (int i = (b); i >= (a); i--)
#define R0F(i, a) ROF(i, 0, a-1)
#define rep(a) F0R(_, a)
#define each(a, x) for (auto &a : x)
#define ALL(x) (x).begin(),(x).end()
#define pq priority_queue <li, vector <li>, greater <li>>
using namespace std;
const int maxn=2e5+5;
//const int MOD=1e9+7;
//const int MOD=998244353;
//const int dx[4]{1, 0, -1, 0}, dy[4]{0, 1, 0, -1};
int n;
vector<int> ke[maxn];

ll a[maxn];
ll subtree[maxn];
ll dp[maxn];
ll total,ans;

void dfs(int u,int p,int depth){
  subtree[u]=a[u];
  dp[1]+=depth*a[u];
  for(int v:ke[u]){
    if(v==p) continue;
    dfs(v,u,depth+1);
    subtree[u]+=subtree[v];
  }
}

void dfs2(int u,int p){
  for(int v:ke[u]){
    if(v==p) continue;
    dp[v]=dp[u]+total-2*subtree[v];
    ans=max(ans,dp[v]);
    dfs2(v,u);
  }
}


void solve(){
  cin>>n;
  for(int i=1;i<=n;i++){
    cin>>a[i];
    total+=a[i];
  }
  for(int i=1;i<n;i++){
    int u,v;
    cin>>u>>v;
    ke[u].pb(v);
    ke[v].pb(u);
  }

  dfs(1,0,0);
  ans=dp[1];

  dfs2(1,0);
  cout<<ans;
  return;
}
signed main(){
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);cout.tie(NULL);
  if (fopen("TASK.INP", "r")){
      freopen("TASK.INP", "r", stdin);
      freopen("TASK.OUT", "w", stdout);
  }
  int ntest;
  ntest=1;
  //cin>>ntest;

  for(int i=1;i<=ntest;i++) solve();
  cerr<<"\n"<<"Time elapsed "<<TIME<<"s.\n";
  return 0;
}