#include<bits/stdc++.h>
const int N=1e6+5;
using namespace std;
int n,m,a[N],cnt[N],f[N];
struct node
{
	int x,id;
	bool operator<(const node&b)const{return x==b.x?id<b.id:x<b.x;}
}b[N];
struct ask
{
	int l,r,val;
	bool operator<(const ask&b)const{return r<b.r;}
}q[N*2];int len;
struct BIT
{
	int tr[N];
	void add(int x,int k){for(int i=x;i<N;i+=(i&-i))tr[i]+=k;}
	int query(int x){int res=0;for(int i=x;i;i-=(i&-i))res+=tr[i];return res;}
}T;
int ans;
void clear()
{
	len=0;ans=0;
	for(int i=n;i>=1;i--)if(f[a[i]]){T.add(f[a[i]],-1);f[a[i]]=0;}
	for(int i=1;i<=2*n+2;i++)cnt[i]=0;
}
int li[N],Len;
void solve()
{
	clear();
	cin>>n>>m;Len=2*n;
	for(int i=1;i<=n;i++)cin>>a[i],li[i]=a[i],li[n+i]=a[i]+1;
	li[++Len]=1;li[++Len]=2;
	sort(li+1,li+Len+1);
	Len=unique(li+1,li+Len+1)-li-1;
	for(int i=1;i<=n;i++)a[i]=lower_bound(li+1,li+Len+1,a[i])-li;
	for(int i=1;i<=n;i++)b[i].x=a[i],b[i].id=i,cnt[a[i]]++,ans+=(cnt[a[i]]==1);
	int temp=1;while(cnt[temp])temp++;for(int i=1;i<=n;i++)cnt[a[i]]=0;ans-=temp;
	sort(b+1,b+n+1);
	for(int l=1,r=1;l<=n;l=r+1)
	{
		while(b[l].x==b[r+1].x)r++;
		if(b[l].x!=b[l-1].x+1)break;
		for(int i=l;i<=r;i++)
		{
			if(i==l)
			{
				if(b[l].id!=1){++len;q[len].l=1;q[len].r=b[l].id-1;q[len].val=b[l].x;}
				continue;
			}
			if(b[i-1].id+1!=b[i].id)
			{++len;q[len].l=b[i-1].id+1;q[len].r=b[i].id-1;q[len].val=b[l].x;}
		}
		if(b[r].id!=n){++len;q[len].l=b[r].id+1;q[len].r=n;q[len].val=b[l].x;}
	}
	sort(q+1,q+len+1);
	for(int i=1,next=1;i<=len;i++)
	{
		for(int j=next;j<=q[i].r;j++)
		{
			if(f[a[j]])T.add(f[a[j]],-1);
			T.add(j,1);
			f[a[j]]=j;
		}
		next=q[i].r+1;
		ans=max(ans,T.query(q[i].r)-T.query(q[i].l-1)-q[i].val);
	}
	cout<<ans<<'\n';
}
int TT;
int main()
{
//	freopen("27.in","r",stdin);
//	freopen("mex.out","w",stdout);
	ios::sync_with_stdio(false);cin.tie(0);
	cin>>TT;
	while(TT--)solve();
}