#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int mod=1e9+7;
const int N=1e6+1;
vector<int> g[N];
ll dp[N];
ll answ;
ll a[N];
int n;
void dfs(int v,int p){
    dp[v]=(dp[p]^a[v]);
    answ+=dp[v];
    for(auto i:g[v]){
        if(i!=p){
            dfs(i,v);
        }
    }
}
int main(){
    cin>>n;
    for(int i=1;i<=n;++i){
        cin>>a[i];
    }
    for(int i=1;i<n;++i){
        int u,v;
        cin>>u>>v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    for(int i=1;i<=n;++i){
        dfs(i,0);
        answ+=a[i];
    }
    cout<<answ/2;
    return 0;
}
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... |