#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
const ll inf=1.1e18;
namespace io{
    const int S=1<<20;
    char ib[S],*s=ib,*t=ib;
    inline char gc(){ return (s==t)&&(t=(s=ib)+fread(ib,1,S,stdin)),s==t?-1:*s++; }
    inline ll read(){
        ll x=0,f=1;char c=gc();
        while(c<'0'||c>'9') f=(c=='-')?-1:1,c=gc();
        while(c>='0'&&c<='9') x=(x<<3)+(x<<1)+(c&15),c=gc();
        return x*f;
    }
    char ob[S],*p=ob;
    inline void flush(){fwrite(ob,p-ob,1,stdout),p=ob;}
    inline void pt(char x){(p-ob>=S)&&(flush(),1);*p++=x;}
    inline void write(ll x){
        static char t[46];static int ct=0;
        if(x<0) pt('-'),x=-x;
        do{t[++ct]=x%10+'0';x/=10;}while(x);
        while(ct) pt(t[ct]),ct--;
    }
}
using io::read;using io::pt;using io::write;
const int N=3e5+10,p=998244353,iv2=(p+1)>>1;
inline void ad(int &x,int y){(x+=y)>=p&&(x-=p);}
inline int qpow(int x,int y){
    int s=1;while(y){
        if(y&1) s=1ll*s*x%p;
        x=1ll*x*x%p;y>>=1;
    }return s;
}
int n,a[N],id[N],sz[N],zs[N],d[N],f[N],s[N];vi to[N];
inline void dfs(int x,int fa){
    sz[x]=d[x]=1;f[x]=fa;
    for(int y:to[x]){
        if(y==fa) continue;
        dfs(y,x);sz[x]+=sz[y];ad(s[x],s[y]),d[x]=1ll*d[x]*(d[y]+1)%p*iv2%p;
        if(sz[y]>sz[zs[x]]) zs[x]=y;
    }ad(s[x],d[x]);
}
int dfn[N],w[N],ct,top[N],ed[N],dp[N],S[N];
inline void dfs2(int x){
    w[dfn[x]=++ct]=x;dp[x]=1;
    if(zs[x]) top[zs[x]]=top[x],dfs2(zs[x]),ed[x]=ed[zs[x]];
    else ed[x]=x;
    for(int y:to[x]){
        if(y==f[x]||y==zs[x]) continue;
        top[y]=y;dfs2(y);dp[x]=1ll*dp[x]*(d[y]+1)%p*iv2%p;ad(S[x],s[y]);
    }if(zs[x]) dp[x]=1ll*dp[x]*iv2%p;
}
struct DP{
    int d[2][2];
    inline DP(){d[0][0]=d[0][1]=d[1][0]=d[1][1]=0;}
    inline DP(int x,int y){d[0][0]=d[0][1]=d[1][0]=d[1][1]=x,ad(d[1][0],y);}
    DP operator * (DP x){
        DP y;
        y.d[0][0]=(d[0][0]+1ll*d[0][1]*x.d[0][0])%p;
        y.d[0][1]=1ll*d[0][1]*x.d[0][1]%p;
        y.d[1][0]=(d[1][0]+1ll*d[1][1]*x.d[0][0]+x.d[1][0])%p;
        y.d[1][1]=(1ll*d[1][1]*x.d[0][1]+x.d[1][1])%p;
        return y;
    } 
    inline void out(){cout<<d[0][0]<<" "<<d[0][1]<<" "<<d[1][0]<<" "<<d[1][1]<<endl;}
}t[N<<2];
inline void pu(int p){ t[p]=t[p<<1|1]*t[p<<1];}
void build(int p,int l,int r){
    if(l==r) return t[p]=DP(dp[w[l]],S[w[l]]),void();
    int mid=(l+r)>>1;
    build(p<<1,l,mid),build(p<<1|1,mid+1,r);pu(p);
}
void add(int p,int l,int r,int x,int y,int z){
    // cout<<"add:"<<p<<" "<<l<<" "<<r<<" "<<x<<endl;t[p].out();
    if(l==r) return t[p]=DP(y,z),/*cout<<"change:"<<p<<" ",t[p].out(),*/void();
    int mid=(l+r)>>1;
    x<=mid?add(p<<1,l,mid,x,y,z):add(p<<1|1,mid+1,r,x,y,z);pu(p);
    // cout<<"up:"<<p<<" ";t[p].out();
}
DP ask(int p,int l,int r,int pl,int pr){
    if(pl<=l&&r<=pr) return t[p];
    int mid=(l+r)>>1;
    if(mid>=pr) return ask(p<<1,l,mid,pl,pr);
    if(mid<pl) return ask(p<<1|1,mid+1,r,pl,pr);
    return ask(p<<1|1,mid+1,r,pl,pr)*ask(p<<1,l,mid,pl,pr);
}
int v[N],ans;
inline void del(int x){
    // cout<<"del :"<<x<<endl;
    int y;DP tp;v[x]=1;
    while(x){
        add(1,1,n,dfn[x],v[x]?0:dp[x],S[x]);
        y=top[x],tp=ask(1,1,n,dfn[y],dfn[ed[y]]);
        if(f[y]) dp[f[y]]=1ll*dp[f[y]]*qpow((d[y]+1),p-2)%p,ad(S[f[y]],p-s[y]);
        s[y]=tp.d[1][0],d[y]=tp.d[1][1];x=f[y];
        if(f[y]) dp[f[y]]=1ll*dp[f[y]]*(d[y]+1)%p,ad(S[f[y]],s[y]);
    }
    // cout<<"del end:"<<endl;
    // for(int i=1;i<=n;i++) cout<<s[i]<<" "<<d[i]<<" "<<S[i]<<" "<<dp[i]<<endl;
}
inline bool cmp(int x,int y){return a[x]^a[y]?a[x]<a[y]:x<y;}
int main(){
    // freopen("1.in","r",stdin);
    // freopen("1.out","w",stdout);
    n=read();
    for(int i=1;i<=n;i++) a[i]=read(),id[i]=i;
    sort(id+1,id+1+n,cmp);
    for(int i=1,x,y;i<n;i++) x=read(),y=read(),to[x].push_back(y),to[y].push_back(x);
    dfs(1,0),top[1]=1,dfs2(1);build(1,1,n);
    // for(int i=1;i<=n;i++) cout<<s[i]<<" "<<d[i]<<" "<<S[i]<<" "<<dp[i]<<" "<<id[i]<<endl;
    ans=1ll*(s[1]+d[1])*iv2%p*a[id[1]]%p;
    for(int i=1;i<n;i++) del(id[i]),ad(ans,1ll*(s[1]+d[1])*iv2%p*(a[id[i+1]]-a[id[i]])%p);
    printf("%lld\n",1ll*ans*qpow(2,n-1)%p);
    return 0;
}