#include<bits/stdc++.h>
#define LL long long
#define pb push_back
#define SZ(x) ((int)x.size()-1)
#define ms(a,b) memset(a,b,sizeof a)
#define F(i,a,b) for (int i=(a);i<=(b);++i)
#define DF(i,a,b) for (int i=(a);i>=(b);--i)
//#define mp make_pair
//#define OO(x) fixed<<setprecision(x)
using namespace std;
//mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
inline int read(){
	char ch=getchar(); int w=1,c=0;
	for(;!isdigit(ch);ch=getchar()) if (ch=='-') w=-1;
	for(;isdigit(ch);ch=getchar()) c=(c<<1)+(c<<3)+(ch^48);
	return w*c;
}
const int M=1e6+10;

struct fwt{
	int t[M],n;
	#define lowbit(x) (x&-x)
	void init(int _n){
		n=_n;
		F(i,0,n) t[i]=0;
	}
	void add(int x,int y){
		for (;x<=n;x+=lowbit(x)) t[x]+=y;
	}
	int qry(int x){
	    int ret=0;
	    for (;x;x^=lowbit(x)) ret+=t[x];
	    return ret;
	}
	
	inline int kth(int k){
	    int pos=0;
	    int cur=0;
	    DF(i,18,0){//attention!!!!
			pos^=(1<<i);
			if (pos>n || k<=t[pos]) pos^=(1<<i);
			else k-=t[pos];
		}
	    return pos+1;
	}
}A;



int n,m;
int a[M],cur[M];
struct node{
	int l,r,d;
};
vector<int> v[M];
vector<node> t[M];
bool tag[M];
void work(){
	n=read(); m=read();
	F(i,1,n) t[i].clear();
	F(i,1,n){
		a[i]=read();
		v[a[i]].pb(i);
	}
	F(i,1,n){
		if (!tag[a[i]]){
			v[a[i]].pb(n+1);
			int la=0; 
			for (int x:v[a[i]]){
	//			if (!x) continue;
				t[x-1].pb((node){la+1,x-1,a[i]});
				la=x;			
			}
			tag[a[i]]=1;
		}
	
	}
	A.init(n);
	
	int ans=-1e9;int o=0;
	F(i,1,n){
		if (cur[a[i]]) A.add(cur[a[i]],-1);
		else o++;
		cur[a[i]]=i;
		A.add(i,1);
		for (auto O:t[i]){
			if (O.l<=O.r){
//				cerr<<O.l<<" "<<O.r<<" "<<A.qry(i)-A.qry(O.l-1)<<" "<<O.d<<" interval !!\n";
				ans=max(ans,A.qry(i)-A.qry(O.l-1)-O.d);
			}
		}
	}
	
	ans=max(ans,o-m-1);
	cout<<ans<<"\n";	
	F(i,1,n) cur[a[i]]=0;
	F(i,1,n) v[a[i]].clear(),tag[a[i]]=0;

}
int main(){
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	int T=read();
	while (T--) work(); return 0;
	return 0;
}
/* stuff you should look for
	* int overflow, array bounds
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
	* DON'T GET STUCK ON ONE APPROACH
*/