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- //template
- #include<bits/stdc++.h>
- //#include<ext/pb_ds/assoc_container.hpp>
- //#include<ext/pb_ds/tree_policy.hpp>
- //#include <ext/pb_ds/trie_policy.hpp>
- //using namespace __gnu_pbds;
- using namespace std;
- //typedef tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> pbds;
- //typedef trie<string,null_type,trie_string_access_traits<>,pat_trie_tag,trie_prefix_search_node_update> pbtrie;
- #define ll long long int
- #define ld long double
- #define mod 1000000007
- #define inf 1e18
- #define endl "\n"
- #define pb push_back
- #define vi vector<ll>
- #define vs vector<string>
- #define pii pair<ll,ll>
- #define ump unordered_map
- #define mp make_pair
- #define pq_max priority_queue<ll>
- #define pq_min priority_queue<ll,vi,greater<ll> >
- #define all(n) n.begin(),n.end()
- #define ff first
- #define ss second
- #define mid(l,r) (l+(r-l)/2)
- #define bitc(n) __builtin_popcount(n)
- #define SET(a) memset( a, -1, sizeof a )
- #define CLR(a) memset( a, 0, sizeof a )
- #define Pi 3.141592653589793
- #define loop(i,a,b) for(int i=(a);i<=(b);i++)
- #define looprev(i,a,b) for(int i=(a);i>=(b);i--)
- #define _fast ios_base::sync_with_stdio(0); cin.tie(0);
- #define iter(container,it) for(__typeof(container.begin()) it = container.begin(); it != container.end(); it++)
- #define log(args...) {string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
- #define logarr(arr,a,b) for(int z=(a);z<=(b);z++) cout<<(arr[z])<<" ";cout<<endl;
- template <typename T> T gcd(T a, T b){if(a%b) return gcd(b,a%b);return b;}
- template <typename T> T lcm(T a, T b){return (a*(b/gcd(a,b)));}
- vs tokenizer(string str,char ch) {std::istringstream var((str)); vs v; string t; while(getline((var), t, (ch))) {v.pb(t);} return v;}
- void err(istream_iterator<string> it) {}
- template<typename T, typename... Args>
- void err(istream_iterator<string> it, T a, Args... args) {
- cout << *it << " = " << a << endl;
- err(++it, args...);
- }
- void fileIO() {
- #ifndef ONLINE_JUDGE
- freopen("input.txt", "r", stdin);
- freopen("output.txt", "w", stdout);
- #endif
- }
- vector<vi> adj;
- vi w;
- struct trio {
- ll inv, zeros, ones;
- trio() {
- inv = 0,zeros=0,ones=0;
- }
- };
- bool cmp (const trio &a, const trio &b) {
- return a.ones*b.zeros < a.zeros*b.ones;
- }
- trio dfs (ll nd=1, ll par=0) {
- trio cur;
- vector<trio> subtr;
- for (ll child : adj[nd]) {
- if (child != par)
- subtr.pb(dfs(child,nd));
- }
- sort(subtr.begin(),subtr.end(),cmp);
- if (w[nd] == 1) cur.ones++;
- else cur.zeros++;
- for (trio &t : subtr) {
- cur.inv += t.inv; // Intra count of inversions
- cur.inv += cur.ones * t.zeros; // Inter count
- cur.zeros += t.zeros;
- cur.ones += t.ones;
- }
- return cur;
- }
- void solve() {
- ll n; cin >> n;
- adj.clear();
- adj.resize(n+1);
- w.resize(n+1);
- loop (i,1,n) cin >> w[i];
- loop (i,0,n-1) {
- ll u,v; cin >> u >> v;
- adj[u].pb(v);
- adj[v].pb(u);
- }
- trio ans = dfs();
- cout << ans.inv << "\n";
- }
- int main(int argc, char const *argv[]){
- _fast
- //fileIO();
- ll t; cin>>t;
- while(t--){
- solve();
- }
- return 0;
- }
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