#include<cstdio>
#include<cstring>
#include<algorithm>
#define MAXN 100000
#define MAXA 1000000
using namespace std;
void Read(int &x){
    char c;
    while(c=getchar(),c!=EOF)
        if(c>='0'&&c<='9'){
            x=c-'0';
            while(c=getchar(),c>='0'&&c<='9')
                x=x*10+c-'0';
            ungetc(c,stdin);
            return;
        }
}
int fa[MAXA+10],fb[MAXA+10],n,a[MAXN+10],b[MAXN+10],m,ans,T;
void read(){
    Read(n),Read(m);
    int i;
    for(i=1;i<=n;i++)
        Read(a[i]);
    for(i=1;i<=m;i++)
        Read(b[i]);
}
void solve(){
    int i;
    ans=0;
    for(i=n;i;i--)
        fa[a[i]]=fa[a[i]+1]+1;
    for(i=m;i;i--)
        fb[b[i]]=fb[b[i]+1]+1;
    for(i=n;i;i--)
        ans=max(min(fa[a[i]],fb[a[i]]),ans);
    printf("%d\n",ans);
    for(i=n;i;i--)
        fa[a[i]]=0;
    for(i=m;i;i--)
        fb[b[i]]=0;
}
int main()
{
    Read(T);
    while(T--){
        read();
        solve();
    }
}