https://www.cometoj.com/contest/42/problem/B

思路：n很小一定想想可不可以暴力dfs；

#include<algorithm>
#include<set>
#include<queue>
#include<cmath>
#include<cstring>
#include<iostream>
#include<set>
#include<vector>
#include<queue>
#include<cmath>
#include<cstdio>
#include<map>
#include<stack>
#include<string>
#include<bits/stdc++.h>
using namespace std;

#define sfi(i) scanf("%d",&i)
#define sfs(i) scanf("%s",(i))
#define pri(i) printf("%d\n",i)
#define sff(i) scanf("%lf",&i)
#define ll long long
#define ull unsigned long long
#define mem(x,y) memset(x,y,sizeof(x))
#define INF 0x3f3f3f3f
#define eps 1e-16
#define PI acos(-1)
#define lowbit(x) ((x)&(-x))
#define zero(x) (((x)>0?(x):-(x))<eps)
#define fl() printf("flag\n")
#define MOD(x) ((x%mod)+mod)%mod
#define endl '\n'
#define pb push_back
#define lson rt<<1,l,mid
#define rson rt<<1|1,mid+1,r
#define FAST_IO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0)

const int maxn=1e3+9;
const int mod=1e9+7;

inline ll read()
{
    ll f=1,x=0;
    char ss=getchar();
    while(ss<'0'||ss>'9')
    {
        if(ss=='-')f=-1;ss=getchar();
    }
    while(ss>='0'&&ss<='9')
    {
        x=x*10+ss-'0';ss=getchar();
    }    return f*x;
}

int ans=0;
int a[100];
int tmp[100];
int n;
void dfs(int pos,int len)
{
    if(pos>n)
    {
        /*for(int i=1;i<=len-1;i++)
        {
            cout<<tmp[i]<<" ";
        }
        cout<<endl;*/
        bool f=1;
        for(int i=1;i<=len-1;i++)
        {
            int g=tmp[i];
            for(int j=1;j<=len-1;j++)
            {
                if(i!=j)
                {
                    if(__gcd(g,tmp[j])!=1)
                    {
                        f=0;
                        break;
                    }
                }
            }
            if(!f) break;
        }
        /*if(f&&len==6)
        {
            for(int i=1;i<=len-1;i++)
            {
                cout<<tmp[i]<<" ";
            }
            cout<<endl;

        }*/
        if(f) ans=max(ans,len-1);
        return;
    }

    tmp[len]=a[pos];
    dfs(pos+1,len+1);
    dfs(pos+1,len);
}

int main()
{
    FAST_IO;
    //freopen("input.txt","r",stdin);

    int t;
    cin>>t;
    while(t--)
    {
        ans=0;
        cin>>n;
        for(int i=1;i<=n;i++) cin>>a[i];

        dfs(1,1);

        cout<<ans<<endl;
    }

}