#pragma GCC optimize(3,"Ofast","inline")
#pragma GCC optimize(2)
#include<iostream>
#include<vector>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<string>
#include<cctype>
#include<queue>
#include<stack>
using namespace std;
typedef long long ll;
const int maxn=1e6;
int arr[maxn];
int main()
{
int t;
scanf("%d",&t);
while(t--){
int n,x;
scanf("%d%d",&n,&x);
memset(arr,-1,sizeof(arr));
for(int i=0;i<n;i++)scanf("%d",&arr[i]);
int len=0;
int i,j;
for(i=0;i<(1<<n);i++){
int num=0;
ll sum=0;
for(j=0;j<n;j++){
if(i&(1<<j)){
sum+=arr[j];
num++;
}
}
if((sum%x)!=0){
len=max(len,num);
}
}
if(len>0){
printf("%d\n",len);
}else{
printf("-1\n");
}
}
return 0;
}