不是取GCD嘛，为什么题解直接最小值能过，我取GCD不能过

#include <iostream>
using namespace std;
long long a[100005];
const long long mod = 1e9 + 7;
long long gcd(long long a, long long b)
{
	while (b)
	{
		int r = a;
		a = b;
		b = r % b;
	}
	return a;
}
int main()
{
	int n;
	cin >> n;
	cin >> a[1];
	long long num = a[1];
	for (int i = 2;i <= n;i++)
	{
		cin >> a[i];
		num = gcd(num, a[i]);
	}
	long long ans = 1;
	for (int i = 1;i <= n;i++)
	{
		ans = ans * (a[i] / num);
		ans %= mod;
	}
	cout << num << " " << ans << endl;
	return 0;
}

#include <iostream>
using namespace std;
int a[100050],n,mgcd=1<<30;
const int mod=1e9+7;
int main()
{
    cin >> n;
    for (int i=1;i<=n;i++)
    {
        cin >> a[i];
        mgcd=min(mgcd,a[i]);
    }
    long long ans=1;
    for (int i=1;i<=n;i++)
        ans=(long long)ans*(a[i]/mgcd)%mod;
    cout << mgcd << " " << ans << endl;
    return 0;
}

输入：
3
6 10 15

我的输出：
1 900

题解输出：
6 2