#include<bits/stdc++.h>
using namespace std;
int read(){
    char c;int res=0;
    while(!isdigit(c=getchar()));
    res=c-'0';
    while(isdigit(c=getchar()))
        res=res*10+c-'0';
    return res;
}
const int N=1000005;
int n,a[N]; vector<int> G[N];

#define out(x) cerr<<#x<<'='<<x<<' '
#define outln(x) cerr<<#x<<"="<<x<<"\n"
#define sz(x) (int)(x).size()
typedef long long ll;
const int inf=(int)1e9;

int ans=0,dep[N],mi1[N],mi2[N];
void dfs(int u,int f){
    mi1[u]=a[u]+dep[u],mi2[u]=-a[u]+dep[u];
    for(auto &v : G[u]) if(v!=f){
        dep[v]=dep[u]+1;
        dfs(v,u);
        mi1[u]=min(mi1[u],mi1[v]);
        mi2[u]=min(mi2[u],mi2[v]);
    }
    ans=min(ans,mi1[u]+mi2[u]-2*dep[u]+1);
}

void init(){
    n=read(); ans=inf;
    for(int i=1;i<=n;i++) a[i]=read(),G[i].clear();
    for(int i=1;i<n;i++){
        int x=read(),y=read();
        G[x].push_back(y); G[y].push_back(x);
    }
    dfs(1,0);
    printf("%d\n",ans);
}
 
void solve(){
    // outln(s[1]);
}

int main(){
    int T=read();
    while(T--){init(); solve();}
    return 0;
}