write a go solution for Description:
You are given n integers a_1,a_2,...,a_n, such that for each 1<=i<=n holds i-n<=a_i<=i-1.

Find some nonempty subset of these integers, whose sum is equal to 0. It can be shown that such a subset exists under given constraints. If there are several possible subsets with zero-sum, you can find any of them.

Input Format:
Each test contains multiple test cases. The first line contains the number of test cases t (1<=t<=10^6). The description of the test cases follows.

The first line of each test case contains a single integer n (1<=n<=10^6).

The second line of each test case contains n integers a_1,a_2,...,a_n (i-n<=a_i<=i-1).

It is guaranteed that the sum of n over all test cases does not exceed 10^6.

Output Format:
For each test case, output two lines.

In the first line, output s (1<=s<=n) — the number of elements in your subset.

In the second line, output s integers i_1,i_2,...,i_s (1<=i_k<=n). All integers have to be pairwise different, and a_i_1+a_i_2+...+a_i_s has to be equal to 0. If there are several possible subsets with zero-sum, you can find any of them.

Note:
In the first example, we get sum is a_1=0.

In the second example, we get sum is a_1+a_4+a_3+a_2=0.. Output only the code with no comments, explanation, or additional text.