#include<bits/stdc++.h>
#define For(i,j,k) for(int i=(j);i<=(k);i++)
#define foR(i,j,k) for(int i=(j);i>=(k);i--) 
#define vi vector<int>
#define pb push_back
#define pii pair<int,int> 
#define mkp make_pair
#define SZ(x) ((int)x.size())

using namespace std;
inline int read() {
	char c;int res=0;bool flag=0;
	while(c=getchar(),c<48)(c=='-')&&(flag=1);
	do res=(res<<3)+(res<<1)+(c^48);
	while(c=getchar(),c>47);
	flag&&(res=-res); return res; 
}
const int MN=1e6+5; 
vi e[MN]; int n,a[MN],siz[MN],vis[MN],vrt,rt,ans=1; 
void getroot(int u,int fa,int allsiz) {
	siz[u]=1; 
	int mx=0; 
	for(auto v:e[u]) {
		if(vis[v]||v==fa) continue; 
		getroot(v,u,allsiz);
		siz[u]+=siz[v]; mx=max(mx,siz[v]); 
	}
	mx=max(mx,allsiz-siz[u]); 
	if(rt==-1||vrt>mx) vrt=mx,rt=u; 
}
int mn1,mn2,mn3,mn4;  
void get(int u,int fa,int mn,int mx,int dep) {
	mn=min(mn,a[u]); mx=max(mx,a[u]); 
	mn1=min(dep-mx,mn1),mn2=min(dep+mn,mn2);
	ans=min(ans,dep+1-mx+mn); 
	for(auto v:e[u]) {
		if(v==fa||vis[v]) continue; 
		get(v,u,mn,mx,dep+1); 	
	}
}
void solve(int u) {
	mn3=(1<<30),mn4=(1<<30); 
	for(auto v:e[u]) {
		if(vis[v]) continue; 
		mn1=(1<<30),mn2=(1<<30); 
		get(v,u,a[u],a[u],1); 	
		ans=min(ans,min(mn1+mn4+1,mn2+mn3+1));
		mn3=min(mn3,mn1),mn4=min(mn4,mn2); 
	}
	
}
void dfs(int u,int allsiz) {
	vis[u]=1; 
	solve(u); 
	for(auto v:e[u]) {
		if(vis[v]) continue; 
		int t=(siz[v]<siz[u])?siz[v]:allsiz-siz[u]; 
		vrt=(1<<30); getroot(v,u,t); 
		dfs(rt,t); 
	}
}

void works() {
	ans=1; 
	n=read(); 
	For(i,1,n) e[i].clear(),vis[i]=0; 
	For(i,1,n) a[i]=read();
	For(i,1,n-1) {
		int u=read(),v=read();
		e[u].pb(v),e[v].pb(u); 	
	}
	dfs(1,n); 
//	cerr<<"?";
	printf("%d\n",ans); 
}
signed main() {
	#ifdef wasa855
		freopen("pro.in","r",stdin); 
		freopen("pro.out","w",stdout); 
	#endif
	int T=read(); 
	while(T--) {
		works(); 	
	}
	return 0; 	
}