#pragma comment(linker, "/STACK:1024000000,1024000000")#include<cstdio>#include<cstring>#include<cmath>#include<algorithm>#include<vector>#include<map>#include<set>#include<queue>#include<stack>#include<iostream>using namespace std;typedef long long LL;const double pi=acos(-1.0),eps=1e-6;void File(){    freopen("D:\\in.txt","r",stdin);    freopen("D:\\out.txt","w",stdout);}template <class T>inline void read(T &x){    char c=getchar(); x=0;    while(!isdigit(c)) c=getchar();    while(isdigit(c)) {x=x*10+c-‘0‘; c=getchar();}}const int maxn=100010;int dp[10*maxn],f[10*maxn],n,m;int s1[10*maxn],s2[10*maxn];int main(){    int T; scanf("%d",&T);    for(int cas=1;cas<=T;cas++)    {        dp[0]=0; f[0]=0; s1[0]=cas; s2[0]=cas;        scanf("%d%d",&n,&m);        for(int i=1;i<=n;i++)        {            int x; scanf("%d",&x);            if(s1[x]<cas) s1[x]=cas, dp[x]=0;            if(s1[x-1]<cas) dp[x-1]=0;            dp[x]=max(dp[x],dp[x-1]+1);        }        int ans=0;        for(int i=1;i<=m;i++)        {            int x; scanf("%d",&x);            if(s2[x]<cas) s2[x]=cas, f[x]=0;            if(s2[x-1]<cas) f[x-1]=0;            f[x]=max(f[x],f[x-1]+1);            if(s1[x]<cas) dp[x]=0;            int pp=min(f[x],dp[x]);            ans=max(ans,pp);        }        printf("%d\n",ans);    }    return 0;}