#include<bits/stdc++.h>
#define p_b push_back
#define m_p make_pair
#define pii pair<int,int>
//#define int long long
#define ls k<<1
#define rs k<<1|1
#define mid ((l+r)>>1)
#define gcd __gcd
#define lowbit(x) (x&(-x))
using namespace std;
int rd(){
	int x=0,f=1; char ch=getchar();
	for(;ch<'0'||ch>'9';ch=getchar())if (ch=='-') f=-1;
	for(;ch>='0'&&ch<='9';ch=getchar())x=(x<<1)+(x<<3)+(ch^48);
	return x*f;
}
const int N=1e6+5,INF=0x3f3f3f3f;
int n,m,a[N],b[N];
struct BIT{
	int c[N<<1];
	void clean(){
		for(int i=1;i<=max(n,m)*2+1;i++) c[i]=-INF;
	}
	void add(int x,int y){
		x+=max(n,m)+1;
		for(;x<=max(n,m)*2+1;x+=lowbit(x)) c[x]=max(c[x],y);
	}
	int query(int x){
		x+=max(n,m)+1;
		int res=-INF;
		while(x){
			res=max(res,c[x]);
			x-=lowbit(x);
		}
		return res;
	}
}Ta,Tb;
int suma[N],sumb[N],sufa[N],sufb[N],prea[N],preb[N];
void solve(){
	n=rd(),m=rd();
	for(int i=1;i<=n;i++) a[i]=rd();
	for(int i=1;i<=m;i++) b[i]=rd();
	
	Ta.clean();Tb.clean();int tmp;
	
	prea[0]=preb[0]=0,sufa[0]=n+1,sufb[0]=m+1;
	for(int i=1;i<=n+1;i++)prea[i]=n+1,sufa[i]=0;
	for(int i=1;i<=m+1;i++)preb[i]=m+1,sufb[i]=0;
	
	for(int i=1;i<=n;i++)suma[i]=suma[i-1]+(a[i]==2);
	tmp=0;
	for(int i=1;i<=n;i++) if(a[i]==1) prea[++tmp]=i;
	tmp=0;
	for(int i=n;i>=1;i--) if(a[i]==3) sufa[++tmp]=i;
	suma[n+1]=suma[n];
	for(int i=1;i<=m;i++)sumb[i]=sumb[i-1]+(b[i]==2);
	tmp=0;
	for(int i=1;i<=m;i++) if(b[i]==1) preb[++tmp]=i;
	tmp=0;
	for(int i=m;i>=1;i--) if(b[i]==3) sufb[++tmp]=i;
	sumb[m+1]=sumb[m];
	int ans=-INF;
	for(int i=min(n,m)+1,j=0;i>=0;i--){
		while(j<=min(n,m)+1&&sufa[j]>prea[i]&&sufb[j]>preb[i]){
			Ta.add(suma[sufa[j]]-sumb[sufb[j]],j+suma[sufa[j]]);
			Tb.add(sumb[sufb[j]]-suma[sufa[j]],j+suma[sufb[j]]);
			j++;
		}
		ans=max(ans,i+max(Ta.query(suma[prea[i]]-sumb[preb[i]])-suma[prea[i]],Tb.query(sumb[preb[i]]-suma[prea[i]])-sumb[preb[i]]));
	}
	printf("%d\n",ans);
}
signed main(){
	int T=rd();
	while(T--)solve();
	return 0;
}