#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <string>
#include <map>
#include <queue>
#include <bitset>
#include <vector>
#include <stack>
#include <cmath>
#include <set>
#include <cstdlib>
#include <unordered_map>
#include <random>
#include <chrono>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/hash_policy.hpp>
using namespace __gnu_pbds;
#define mp make_pair
#define lson tr[now].ls
#define rson tr[now].rs
#define pb push_back
#define debug() cout<<"qwq"<<endl
#define mem(i,a) memset(i,a,sizeof(i))
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
#define i128 __int128
#define pii pair<int,int>
const db eps=1e-10;
const ll INF = 0x3f3f3f3f;
const int siev =1000000+5;
const int inf = 0x3f3f3f3f;
const int DMAX = 30000 + 100;
const int G=3;
const int invG=332748118;
const double PI=acos(-1.0);
const ll MOD = 998244353;
const ll LMOD = 1000000007;
const int hmod = 202010923;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
template<class T> inline void print(T x){
    if(x<0){
        putchar('-');
        x=-x;
    }
    int a[20];
    int cnt=0;
    do{
        a[++cnt]=x%10;
        x/=10;
    }while(x>0);
    for(int i=cnt;i>=1;i--){
        putchar(a[i]+'0');
    }
    putchar('\n');
    // puts("");
}
template<class T> inline void read(T &x){
    x=0;
    T f=1;
    char ch=getchar();
    while(ch<'0' || ch>'9'){
        if(ch=='-'){
            f=-1;
        }
        ch=getchar();
    }
    while(ch<='9' && ch>='0'){
        x=x*10+(ch-'0');
        ch=getchar();
    }
    x*=f;
}
struct Trie{
    struct node{
        int ch[2];
        int hve;
    };
    node nde[DMAX*30];
    int cnt,rt;
    void clear(){
        for(int i=1;i<=1;i++){
            nde[i].ch[0]=nde[i].ch[1]=nde[i].hve=0;
        }
        cnt=1,rt=1;
    }
    void insert(int val){
        int now=rt;
        nde[now].hve++;
        for(int i=20;i>=0;i--){
            int x=((val>>i) & 1);
            if(!nde[now].ch[x]){
                nde[now].ch[x]=++cnt;
                nde[cnt].hve=0;
                nde[cnt].ch[0]=nde[cnt].ch[1]=0;
            }
            now=nde[now].ch[x];
            nde[now].hve++;
        }
        
    }
    int DFS(int x,int y,int tms,int val){
        // cout<<x<<" "<<y<<" "<<tms<<endl;
        if(!x || !y){
            return nde[x|y].hve;
        }
        if(tms==-1){
            if(x==y){
                return nde[x].hve;  
            }
            return nde[x].hve+nde[y].hve;
        }
        int pos=((val>>tms) & 1);
        if(pos==1){
            int red=0;
            red+=DFS(nde[x].ch[0],nde[y].ch[1],tms-1,val);
            if(x!=y){
                red+=DFS(nde[x].ch[1],nde[y].ch[0],tms-1,val);
            }
            return red;
        }
        if(pos==0){
            int red=0;
            red=max(red,DFS(nde[x].ch[0],nde[y].ch[0],tms-1,val));
            red=max(red,DFS(nde[x].ch[1],nde[y].ch[1],tms-1,val));
        //    int red=max(DFS(nde[x].ch[0],nde[y].ch[0],tms-1,val),DFS(nde[x].ch[1],nde[y].ch[1],tms-1,val));
            if(x!=y){
                red=max(red,max(nde[x].hve,nde[y].hve));
            }
            return red;
        }   
        
    }
};
Trie tr;
int T;
int n,k;
int main(){
    read(T);
    while(T--){
        read(n),read(k);
        tr.clear();
        int x;
        for(int i=1;i<=n;i++){
            read(x);
            tr.insert(x);
        }
        int ans=tr.DFS(1,1,20,k);
        print(ans);
    }
    return 0;
}