#include<bits/stdc++.h>
// #define ONLINE_JUDGE
#define INPUT_DATA_TYPE int
#define OUTPUT_DATA_TYPE int
inline __attribute((always_inline)) INPUT_DATA_TYPE read(){register INPUT_DATA_TYPE x=0;register char f=0,c=getchar();while(c<'0'||'9'<c)f=(c=='-'),c=getchar();while('0'<=c&&c<='9')x=(x<<3)+(x<<1)+(c&15),c=getchar();return f?-x:x;}void print(OUTPUT_DATA_TYPE x){if(x<0)x=-x,putchar('-');if(x>9)print(x/10);putchar(x%10^48);return;}


int suma[1000010],sumb[1000010],a[1000010],b[1000010];

void solve(){
    std::vector<int> La,Ra,Lb,Rb;
    register int i,j,res=0,maxi,maxj;
    int n=read();
    int m=read();
    for(i=1;i<=n;++i){
        a[i]=read();
        if(a[i]==1) La.push_back(i);
        else if(a[i]==3) Ra.push_back(i);
        suma[i]=suma[i-1]+(a[i]==2);
    }
    for(i=1;i<=m;++i){
        b[i]=read();
        if(b[i]==1) Lb.push_back(i);
        else if(b[i]==3) Rb.push_back(i);
        sumb[i]=sumb[i-1]+(b[i]==2);
    }
    std::reverse(Ra.begin(),Ra.end());
    std::reverse(Rb.begin(),Rb.end());
    La.insert(La.begin(),0);
    Ra.insert(Ra.begin(),n+1);
    Lb.insert(Lb.begin(),0);
    Rb.insert(Rb.begin(),n+1);
    maxi=std::min({La.size(),Lb.size()})-1;
    maxj=std::min({Ra.size(),Rb.size()})-1;
    
    for(i=0;i<=maxi;++i)
    for(j=0;j<=maxj;++j)
    if(Ra[j]>La[i]&&Rb[j]>Lb[i]){
        res=std::max(res,i+j+std::min(suma[Ra[j]-1]-suma[La[i]],sumb[Rb[j]-1]-sumb[Lb[i]]));
    }
    print(res),putchar('\n');
}

int main(){
	#ifndef ONLINE_JUDGE
	freopen("name.in", "r", stdin);
	freopen("name.out", "w", stdout);
	#endif

    int T=read();
    while(T--) solve();

	#ifndef ONLINE_JUDGE
	fclose(stdin);
	fclose(stdout);
	#endif
    return 0;
}