#include<bits/stdc++.h>
using namespace std;using ll=long long;using ld=long double;using pii=pair<int,int>;
const int M=998244353,P=20;const ll inf=1e17;const double eps=1e-10;
int xt,tc;
bool o;
struct S
{
int n,K,res=0;vector<vector<int>>es;
vector<int>val,lit;
void ini()
{
cin>>n>>K;val.resize(n+1,0);lit=val;for(int i=1;i<=n;i++)cin>>val[i];
if(o)
{
cout<<n<<' '<<k<<'\n';
for(int i=1;i<=n;i++)cout<<val[i]<<" \n"[i==n];
}
es.resize(n+1);
for(int i=1,u,v;i<n;i++)
{
cin>>u>>v,es[u].push_back(v),es[v].push_back(u);
if(o)
{
cout<<u<<' '<<v<<'\n';
}
}
}
struct Ks
{
int sum=0,sp=M;//min_rt1_trs
};
Ks mg(Ks U,Ks D)
{
return Ks{U.sum+D.sum,min(U.sp,D.sp)};
}
Ks spr(int x,int lst)
{
lit[x]=1;Ks A={0,M};int d=0;
for(auto&k:es[x])if(!lit[k])
{
auto p=spr(k,x);
A=mg(A,p);d++;
}
if(d==1&&val[x]==1)
{
if(A.sum+1>=K){res++;return Ks{0,0};}
}
if(val[x]==1)A={A.sum+1,min(A.sp,A.sum+1)};
else A={A.sum+val[x],A.sp};
if(A.sum>=K)
{
if((A.sum-K)%2==0){res++;return Ks{0,0};}
else if(A.sum-A.sp>=K){res++;return Ks{0,0};}
}
return A;
}
void solve()
{
for(int i=1;i<=n;i++)if(!lit[i])spr(i,0);
if(t<=1000)cout<<res<<'\n';
}
};
void precal()
{
}
int main()
{
//freopen("1.in","r",stdin);
//cout<<fixed<<setprecision(12);
ios::sync_with_stdio(0);cin.tie(0);precal();
int t=1;cin>>t;xt=t;
//clock_t a=clock();
while(t--){tc++;o=(tc==32);S SS;SS.ini();SS.solve();}
//cout<<"Time:"<<double(clock()-a)<<'\n';
}
/*
*/