#include<bits/stdc++.h>
using namespace std;
const int N = 1e6;
int n,m,v,ca1,ca3,cb1,cb3,ans;
int la[N + 5],ra[N + 5],sa[N + 5];
int lb[N + 5],rb[N + 5],sb[N + 5];
struct Segment_Tree
{
	#define ls id << 1
	#define rs id << 1 | 1
	int mx[8 * N + 5];
	void update(int id,int l,int r,int x,int v)
	{
		if(l == r)
			return mx[id] = max(mx[id],v),void();
		int mid = l + r >> 1;
		if(x <= mid)update(ls,l,mid,x,v);
		else update(rs,mid + 1,r,x,v);
		mx[id] = max(mx[ls],mx[rs]);
	}
	int query(int id,int l,int r,int st,int en)
	{
		if(l >= st&&r <= en)return mx[id];
		int mid = l + r >> 1,res = 0;
		if(st <= mid)res = max(res,query(ls,l,mid,st,en));
		if(en > mid)res = max(res,query(rs,mid + 1,r,st,en));
		return res;
	}
	void build(int id,int l,int r)
	{
		if(l == r)return mx[id] = 0,void();
		int mid = l + r >> 1;
		build(ls,l,mid);build(rs,mid + 1,r);
		mx[id] = max(mx[ls],mx[rs]);
	}
	#undef ls
	#undef rs
}sta,stb;
void solve()
{
	scanf("%d %d",&n,&m);
	ca1 = ca3 = cb1 = cb3 = 0;
	
	la[++ca1] = 0;
	for(int i = 1;i <= n;i++)
	{
		scanf("%d",&v);
		sa[i] = sa[i - 1];
		if(v == 1)la[++ca1] = i;
		else if(v == 2)sa[i]++;
		else ra[++ca3] = i;
	}
	sa[n + 1] = sa[n];
	ra[++ca3] = n + 1;
	reverse(ra + 1,ra + ca3 + 1);
	
	lb[++cb1] = 0;
	for(int i = 1;i <= m;i++)
	{
		scanf("%d",&v);
		sb[i] = sb[i - 1];
		if(v == 1)lb[++cb1] = i;
		else if(v == 2)sb[i]++;
		else rb[++cb3] = i;
	}
	sb[m + 1] = sb[m];
	rb[++cb3] = m + 1;
	reverse(rb + 1,rb + cb3 + 1);
	
	int now = 1,k = n + m + 1;
	sta.build(1,1,k);stb.build(1,1,k);
	ans = 0;
	for(int i = min(ca1,cb1);i;i--)
	{
		while(now <= min(ca3,cb3)&&ra[now] >= la[i]&&rb[now] >= lb[i])
		{
			sta.update(1,1,k,sa[ra[now]] - sb[rb[now]] + m + 1,sb[rb[now]] + now - 1);
			stb.update(1,1,k,sb[rb[now]] - sa[ra[now]] + n + 1,sa[ra[now]] + now - 1);
			now++;
		}
		int resa = sta.query(1,1,k,sa[la[i]] - sb[lb[i]] + m + 1,k);
		int resb = stb.query(1,1,k,sb[lb[i]] - sa[la[i]] + n + 1,k);
		ans = max(ans,i - 1 + max(resa - sb[lb[i]],resb - sa[la[i]]));
	}
	cout<<ans<<"\n";
}
/*
sa[r] - sa[l] > sb[r] - sb[l]
sa[r] - sb[r] > sa[l] - sb[l]
*/
int main()
{
	int t;
	scanf("%d",&t);
	while(t--)solve(); 
}