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| #include <bits/stdc++.h>
using namespace std;
const double eps = 1e-10; const double pi = 3.1415926535897932384626433832795; const double eln = 2.718281828459045235360287471352;
#define f(i, a, b) for (int i = a; i <= b; i++) #define scan(x) scanf("%d", &x) #define mp make_pair #define pb push_back #define lowbit(x) (x&(-x))
#define fi first #define se second #define SZ(x) int((x).size()) #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define summ(a) (accumulate(all(a), 0ll))
typedef unsigned long long ull; typedef pair<int,int> pii; typedef vector<int> vi;
using ll=long long;
template<typename T> struct BIT{ vector<T> h; int n; BIT(int sz):n(sz),h(sz+1,0){} void update(int x,T val){ while(x<=n){ h[x]+=val; x+=lowbit(x); } } T query(int x){ T res=0; while(x>0){ res+=h[x]; x-=lowbit(x); } return res; } };
ull n,a[(int)5e5+9],dfn_cnt,presum,ans,res[(int)5e5+9]; BIT<int> bit(int(1e6+1)); BIT<ull> bit_sq(int(1e6+1));
int main() { ios::sync_with_stdio(false); cin.tie(0); cin>>n; vector g(n+1,vector<int>()); for(int i=1,x,y;i<n;++i){ cin>>x>>y; g[x].push_back(y),g[y].push_back(x); } for(int i=1;i<=n;++i)cin>>a[i];
vector<int> son(n+1,0), sz(n+1,0), dfn(n+1,0), ori(n+1,0); auto dfs=[&](const auto& self, const vector<vector<int>>&g, int u, int fa)->void{ sz[u]=1, dfn[u]=++dfn_cnt, ori[dfn[u]]=u;
for(auto it:g[u])if(it!=fa){ self(self, g, it, u); sz[u]+=sz[it]; son[u]=sz[son[u]]<sz[it]?it:son[u]; } };
auto dsu=[&](const auto& self, const vector<vector<int>>&g, int u, int fa,int sta)->void{
auto cal=[&](ull cor)->void{ ull f = bit.query(cor); ull e = bit_sq.query(int(1e6))-bit_sq.query(cor); ans+=(cor*cor*f+e-cor*presum)*ull(2); bit.update(cor,1),presum+=cor; bit_sq.update(cor,cor*cor); };
auto del=[&](ull cor)->void{ bit.update(cor,-1); bit_sq.update(cor,-cor*cor); presum -= cor; };
for(auto it:g[u])if(it!=fa&&it!=son[u]){ self(self, g, it, u, 0); } if(son[u])self(self, g, son[u], u, 1); for(auto it:g[u])if(it!=fa&&it!=son[u]){ for(int i=dfn[it];i<dfn[it]+sz[it];++i){ cal(a[ori[i]]); } } cal(a[u]);
res[u]=ans;
if(!sta){ for(int i=dfn[u];i<sz[u]+dfn[u];++i)del(a[ori[i]]); ans=0; } };
dfs(dfs,g,1,0); dsu(dsu,g,1,0,0); for(int i=1;i<=n;++i)ans^=res[i]; cout<<ans; return 0; }
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