#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];
ll pref[N];
ll cnt[N][2];
int n;
int main(){
    cin>>n;
    for(int i=1;i<=n;++i){
        cin>>a[i];
        pref[i]=pref[i-1]^a[i];
        for(int j=0;j<30;++j){
            if(pref[i]&(1<<j)){
                cnt[j][1]++;
            }
            else{
                cnt[j][0]++;
            }
        }
    }
    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){
        for(int j=0;j<=30;++j){
            if((1<<j)&pref[i]){
                ll e=(1<<j);
                e*=pref[i];
                answ+=e;
            }
        }
    }
    cout<<answ/2;
    return 0;
}
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