水4_HDU_5207

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
const int maxn = 100005;
using namespace std;
int d[maxn],n;
int main()
{
int t,ans;
scanf("%d",&t);
for(int k = 1; k <= t; k++)
{
ans = 1;
int x,j = 0;
scanf("%d",&n);
memset(d,0,sizeof(d));
for(int i = 0; i < n; i++)
{
scanf("%d",&x);
for(int j = 1; j*j<=x; j++)
{
if(x%j == 0)
{
d[j]++;
if(x/j != j)
d[x/j]++;
}

}

}
for(int i = 100000;i>=1;i--)
{
if(d[i]>=2)
{
ans = i;
break;
}
}
printf("Case #%d: %d\n",k,ans);
}
return 0;
}