#include<bits/stdc++.h>
#include<atcoder/all>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace atcoder;
using namespace __gnu_pbds;
using mint = modint998244353;
#define Yes(n) cout << ((n) ? "Yes" : "No"  ) << endl
#define print(var) std::cout<<#var<<"="<<(var)<<std::endl
#define all(a) (a).begin(), (a).end()
#define vi vector<int>
#define vvi vector<vi>
#define vvvi vector<vvi>
#define ll long long
#define vll vector<ll>
#define vvll vector<vll>
#define vvvll vector<vvll>
#define vvvvll vector<vvvll>
#define vmi vector<mint>
#define vvmi vector<vmi>
#define vvvmi vector<vvmi>
#define vvvvmi vector<vvvmi>
#define vvvvvmi vector<vvvvmi>
#define vs vector<string>
#define pii pair<int,int>
#define vpii vector<pii>
#define vvpii vector<vpii>
#define bit(x,i)(((x)>>(i))&1)
#define inf (1<<30)
#define INF (1ll<<60)
#define X first
#define Y second
template<typename T> inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); }
template<typename T> inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); }
template<class T, class F> T nibutan(T ok, T ng, const F &f){while(abs(ok-ng)>1){T mid = (ok+ng)/2;(f(mid)?ok:ng) = mid;}return ok;}
template<class T> vector<T> digit(T x){vector<T> res; while(x>0){res.push_back(x%10); x/=10;} return res;}
ostream& operator<<(ostream& os, const mint& x){ os << x.val(); return os; }
template<class T> istream &operator>>(istream &is, vector<T> &vec){ for(auto &v:vec) is >> v; return is; }
template<class T> void coutvector(vector<T> x){ for(int i=0;i<(int)x.size();i++){if(i>0) cout<<" ";cout<<x[i];}cout<<endl;}
using Set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
template<class S, class T> using Unordered_Map = gp_hash_table<S,T>;

#ifdef LOCAL
#include<dump.hpp>
CPP_DUMP_DEFINE_EXPORT_OBJECT(mint,val());
#else
#define cpp_dump
#endif

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n; cin>>n;
    vll a(n); cin>>a;
    vvi g(n);
    for(int i=0;i<n-1;i++){
        int u,v; cin>>u>>v,u--,v--;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    mint ans = 0;
    vmi dp(n,0);
    auto dfs = [&](auto dfs, int tp, int pa)->void{
        mint tmp = 0;
        mint sum = 0;
        for(auto np:g[tp])if(np!=pa){
            dfs(dfs,np,tp);
            dp[tp] += dp[np]+a[np];
            tmp += (dp[np]+a[np])*(dp[np]+a[np]);
            sum += dp[np]+a[np];
        }
        tmp = (sum*sum-tmp)/2;
        tmp *= a[tp];
        ans += tmp;
        dp[tp]*=a[tp];
        ans += dp[tp];
        return;
    };
    dfs(dfs,0,-1);
    cpp_dump(dp);
    cout << ans.val() << endl;
}