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


const int maxn = 2e6 + 10;
int n,m;
struct BIT
{
	int c[maxn];
	int n;
	int lowbit(int x){return x & (-x);}
	void init(int x){n = x;for(int i = 1;i <= 2 * n;i++)c[i] = -1e9;}
	void update(int u,int val)
	{
		u += n;
		while(u <= 2 * n){c[u] = max(val,c[u]);u += lowbit(u);}
	}
	int query(int u)
	{
		int ans = -1e9;
		u += n;
		while(u > 0){ans = max(c[u],ans);u -= lowbit(u);}
		return ans;
	}
}T1,T2;

int la[maxn],lb[maxn],ra[maxn],rb[maxn];
int a[maxn],b[maxn];
int suma[maxn],sumb[maxn];

void solve()
{
	cin >> n >> m;
	for(int i = 1;i <= n;i++)cin >> a[i];
	for(int i = 1;i <= m;i++)cin >> b[i];

	la[0] = 0;
	ra[0] = n + 1;
	lb[0] = 0;
	rb[0] = m + 1;
	for(int i = 1;i <= n;i++)la[i] = n + 1,ra[i] = 0;
	for(int i = 1;i <= m;i++)lb[i] = m + 1,rb[i] = 0;
	for(int i = 1,j = 0;i <= n;i++)if(a[i] == 1)la[++j] = i;
	for(int i = 1,j = 0;i <= m;i++)if(b[i] == 1)lb[++j] = i;
	for(int i = n,j = 0;i >= 0;i--)if(a[i] == 3)ra[++j] = i;
	for(int i = m,j = 0;i >= 0;i--)if(b[i] == 3)rb[++j] = i;
	for(int i = 1;i <= n;i++)suma[i] = suma[i - 1] + (a[i] == 2);
	for(int i = 1;i <= m;i++)sumb[i] = sumb[i - 1] + (b[i] == 2);

	T1.init(max(n,m)),T2.init(max(n,m));
	int ans = 0;
	for(int i = 0,j = min(n,m);j >= 0;j--)
	{
		while(i <= min(n,m) && la[i] < ra[j] && lb[i] < rb[j])
		{
			T1.update(suma[la[i]] - sumb[lb[i]],i - sumb[lb[i]]);
			T2.update(sumb[lb[i]] - suma[la[i]],i - suma[la[i]]);
			i++;
		}
		ans = max(ans,j + sumb[rb[j] - 1] + T1.query(suma[ra[j] - 1] - sumb[rb[j] - 1]));
        ans = max(ans,j + suma[ra[j] - 1] + T2.query(sumb[rb[j] - 1] - suma[ra[j] - 1]));
	}
	cout << ans << '\n';
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);
	int T;cin >> T;while(T--)solve();
	return 0;
}