Array Cloning Technique

Description:

Input:

The input consists of multiple test cases. The first line contains a single integer $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases. Description of the test cases follows.

The first line of each test case contains a single integer $$$n$$$ ($$$1 \le n \le 10^5$$$) — the length of the array $$$a$$$.

The second line of each test case contains $$$n$$$ integers $$$a_1, a_2, \ldots, a_n$$$ ($$$-10^9 \le a_i \le 10^9$$$) — the elements of the array $$$a$$$.

It is guaranteed that the sum of $$$n$$$ over all test cases does not exceed $$$10^5$$$.

Output:

For each test case output a single integer — the minimal number of operations needed to create at least one copy where all elements are equal.

Sample Input:

6
1
1789
6
0 1 3 3 7 0
2
-1000000000 1000000000
4
4 3 2 1
5
2 5 7 6 3
7
1 1 1 1 1 1 1

Sample Output:

0
6
2
5
7
0

Note:

In the first test case all elements in the array are already equal, that's why the answer is $$$0$$$.

In the second test case it is possible to create a copy of the given array. After that there will be two identical arrays:

$$$[ \ 0 \ 1 \ 3 \ 3 \ 7 \ 0 \ ]$$$ and $$$[ \ 0 \ 1 \ 3 \ 3 \ 7 \ 0 \ ]$$$

After that we can swap elements in a way so all zeroes are in one array:

$$$[ \ 0 \ \underline{0} \ \underline{0} \ 3 \ 7 \ 0 \ ]$$$ and $$$[ \ \underline{1} \ 1 \ 3 \ 3 \ 7 \ \underline{3} \ ]$$$

Now let's create a copy of the first array:

$$$[ \ 0 \ 0 \ 0 \ 3 \ 7 \ 0 \ ]$$$, $$$[ \ 0 \ 0 \ 0 \ 3 \ 7 \ 0 \ ]$$$ and $$$[ \ 1 \ 1 \ 3 \ 3 \ 7 \ 3 \ ]$$$

Let's swap elements in the first two copies:

$$$[ \ 0 \ 0 \ 0 \ \underline{0} \ \underline{0} \ 0 \ ]$$$, $$$[ \ \underline{3} \ \underline{7} \ 0 \ 3 \ 7 \ 0 \ ]$$$ and $$$[ \ 1 \ 1 \ 3 \ 3 \ 7 \ 3 \ ]$$$.

Finally, we made a copy where all elements are equal and made $$$6$$$ operations.

It can be proven that no fewer operations are enough.