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

// #define int long long

const int N=1e6+5;

int n,m;
int a[N],b[N];

int la[N],ra[N],sa[N];
int lb[N],rb[N],sb[N];

int lowbit(int x){return x&-x;}

struct BIT{
	int c[N<<1];
	void clear(){
		for(int i=1;i<=max(n,m)*2+1;i++)
			c[i]=0;
	}
	void add(int p,int x){
		p+=max(n,m)+1;
		while(p<=max(n,m)*2+1)
			c[p]=max(c[p],x),p+=lowbit(p);
	}
	int ask(int p){
		p+=max(n,m)+1;
		int res=0;
		while(p)
			res=max(res,c[p]),p-=lowbit(p);
		return res;
	}
}T1,T2;

void Solve(){
	cin>>n>>m;
	for(int i=1;i<=n;i++)cin>>a[i],la[i]=n+1,ra[i]=0;
	for(int i=1;i<=m;i++)cin>>b[i],lb[i]=m+1,rb[i]=0;
	
	ra[0]=n+1,rb[0]=m+1;
	int tmp=0;
	for(int i=1;i<=n;i++){
		if(a[i]==1)
			tmp++,la[tmp]=i;
		sa[i]=sa[i-1]+(a[i]==2);
	}
	tmp=0;
	for(int i=n;i>=1;i--)
		if(a[i]==3)
			tmp++,ra[tmp]=i;
	tmp=0;
	for(int i=1;i<=m;i++){
		if(b[i]==1)
			tmp++,lb[tmp]=i;
		sb[i]=sb[i-1]+(b[i]==2);
	}
	tmp=0;
	for(int i=m;i>=1;i--)
		if(b[i]==3)
			tmp++,rb[tmp]=i;

	T1.clear(),T2.clear();
	int i=0,ans=0;
	for(int j=n;~j;j--){
		if(ra[j]==0||rb[j]==0)
			continue;
		while(i+1<=n&&la[i+1]<ra[j]&&lb[i+1]<rb[j]){
			i++;
			T1.add(sa[la[i]]-sb[lb[i]],i-sb[lb[i]]);
			T2.add(sb[lb[i]]-sa[la[i]],i-sa[la[i]]);
		}
		int val1=j+sb[rb[j]-1]+T1.ask(sa[ra[j]-1]-sb[rb[j]-1]);
		int val2=j+sa[ra[j]-1]+T2.ask(sb[rb[j]-1]-sa[ra[j]-1]);
		ans=max({ans,val1,val2});
	}
	cout<<ans<<'\n';
}

signed main(){

	int T;
	cin>>T;
	while(T--)Solve();

	return 0;
}