#include<bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN=1e6+10,N=1e6;
int n,m,a[MAXN],b[MAXN];
struct BIT{
	int tree[MAXN<<1];
	inline void clear(){memset(tree,0,sizeof tree);}
	inline void init(){memset(tree,-0x3f,sizeof tree);}
	inline int lowbit(int x){return x&(-x);}
	inline void update(int x,int val){for(;x<MAXN*2;x+=lowbit(x)) tree[x]=max(tree[x],val);}
	inline int query(int x){int ans=0; for(;x;x-=lowbit(x)) ans=max(ans,tree[x]); return ans;}
}f1,f2;
int la[MAXN],ra[MAXN],s1[MAXN];
int lb[MAXN],rb[MAXN],s2[MAXN];
int cnta1,cnta3,cntb1,cntb3;
inline void solve(){
	cnta1=cnta3=cntb1=cntb3=0;
	f1.clear(); f2.clear();
	cin>>n>>m;
	for(int i=1;i<=n;i++) cin>>a[i];
	for(int i=1;i<=m;i++) cin>>b[i];
	for(int i=1;i<=n;i++){
		if(a[i]==1) la[++cnta1]=i;
		s1[i]=s1[i-1]+(a[i]==2);
	}
	ra[0]=n+1; for(int i=n;i>=1;i--) if(a[i]==3) ra[++cnta3]=i;
	for(int i=1;i<=m;i++){
		if(b[i]==1) lb[++cntb1]=i;
		s2[i]=s2[i-1]+(b[i]==2);
	}
	rb[0]=m+1; for(int i=m;i>=1;i--) if(b[i]==3) rb[++cntb3]=i;
	f1.init(); f2.init(); int ans=0;
	for(int i=0,j=min(cnta3,cntb3);j>=0;j--){
		while(i<=min(cnta1,cntb1) && ra[j]>la[i] && rb[j]>lb[i]){
			f1.update(-s1[la[i]]+s2[lb[i]]+N,i-s1[la[i]]);
			f2.update(s1[la[i]]-s2[lb[i]]+N,i-s2[lb[i]]);
			i++;
		}
		int res1=f1.query(-s1[max(ra[j]-1,0ll)]+s2[max(rb[j]-1,0ll)]+N)+s1[max(ra[j]-1,0ll)]+j;
		int res2=f2.query(s1[max(ra[j]-1,0ll)]-s2[max(rb[j]-1,0ll)]+N)+s2[max(rb[j]-1,0ll)]+j;
		ans=max({ans,res1,res2});
	}
	cout<<ans<<'\n';
}
signed main(){
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	int T; cin>>T;
	while(T--) solve();
	return 0;
}