#include <bits/stdc++.h>
using namespace std;

long long mod = 998244353;
//入力が必ず-mod<a<modの時.
struct mint{
    long long v = 0;
    mint(){} mint(int a){v = a<0?a+mod:a;} mint(long long a){v = a<0?a+mod:a;}
    mint(unsigned long long a){v = a;}
    long long val(){return v;}
    void modu(){v %= mod;}
 
    mint repeat2mint(const long long a,long long b){
        mint ret = 1,p = a;
        while(b){
            if(b&1) ret *= p;
            p *= p; b >>= 1;
        }
        return ret;
    };
 
    mint &operator=(const mint &b) = default;
    mint operator-() const {return mint(0)-(*this);}
    mint operator+(const mint b){return mint(v)+=b;}
    mint operator-(const mint b){return mint(v)-=b;}
    mint operator*(const mint b){return mint(v)*=b;}
    mint operator/(const mint b){return mint(v)/=b;}
 
    mint operator+=(const mint b){
        v += b.v; if(v >= mod) v -= mod;
        return *this;
    }
    mint operator-=(const mint b){
        v -= b.v; if(v < 0) v += mod; 
        return *this;
    }   
    mint operator*=(const mint b){v = v*b.v%mod; return *this;}
    mint operator/=(mint b){
        if(b == 0) assert(false);
        int left = mod-2;
        while(left){if(left&1) *this *= b; b *= b; left >>= 1;}
        return *this;
    }
 
    mint operator++(int){*this += 1; return *this;}
    mint operator--(int){*this -= 1; return *this;}
    bool operator==(const mint b){return v == b.v;}
    bool operator!=(const mint b){return v != b.v;}
    bool operator>(const mint b){return v > b.v;}
    bool operator>=(const mint b){return v >= b.v;}
    bool operator<(const mint b){return v < b.v;}
    bool operator<=(const mint b){return v <= b.v;}
 
    mint pow(const long long x){return repeat2mint(v,x);}
    mint inv(){return mint(1)/v;}
};

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int N; cin >> N;
    vector<mint> A(N);
    for(auto &a : A) cin >> a.v;

    vector<vector<int>> Graph(N);
    for(int i=0; i<N-1; i++){
        int u,v; cin >> u >> v;
        u--; v--;
        Graph.at(u).push_back(v);
        Graph.at(v).push_back(u);
    }

    vector<bool> stop(N);
    auto findsiz = [&](auto&& self,int pos,int back) -> int {
        if(stop.at(pos)) return 0;
        int ret = 1;
        for(auto to : Graph.at(pos)) if(to != back) ret += self(self,to,pos);
        return ret;
    };
    auto findcent = [&](int start) -> int {
        int siz = findsiz(findsiz,start,-1);
        int cent = -1;
        auto dfs = [&](auto dfs,int pos,int back) -> int {
            if(stop.at(pos)) return 0;
            int ret = 0;
            bool iscent = true;
            for(auto to : Graph.at(pos)) if(to != back){
                int ko = dfs(dfs,to,pos);
                if(ko > siz/2) iscent = false;
                ret += ko;
            } 
            ret++;
            if(siz-ret > siz/2) iscent = false;
            if(iscent) cent = pos;
            return ret;
        };
        dfs(dfs,start,-1);
        return cent;
    };

    mint answer = 0;
    queue<int> Q; Q.push(0);
    mint div2 = mint(1)/2;
    while(Q.size()){
        int start = Q.front(); Q.pop();
        int cent = findcent(start); 

        int n = Graph.at(cent).size();
        vector<mint> sum(n);
        auto dfs = [&](auto dfs,int pos,int back,mint now,int i) -> void {
            if(stop.at(pos)) return;
            now *= A.at(pos);
            sum.at(i) += now;
            for(auto to : Graph.at(pos)) if(to != back) dfs(dfs,to,pos,now,i);
        };
        for(int i=0; i<n; i++) dfs(dfs,Graph.at(cent).at(i),cent,1,i);

        mint all = 0;
        for(auto v : sum) all += v,answer += A.at(cent)*v;
        for(auto v : sum) answer += A.at(cent)*(all*v-v*v)*div2;

        stop.at(cent) = true;
        for(int i=0; i<n; i++){
            int to = Graph.at(cent).at(i);
            if(!stop.at(to)) Q.push(to);
        }
    }
    cout << answer.v << endl;
}