Preparando MOJI
Permutation $$$p$$$ is a sequence of integers $$$p=[p_1, p_2, \dots, p_n]$$$, consisting of $$$n$$$ distinct (unique) positive integers between $$$1$$$ and $$$n$$$, inclusive. For example, the following sequences are permutations: $$$[3, 4, 1, 2]$$$, $$$[1]$$$, $$$[1, 2]$$$. The following sequences are not permutations: $$$[0]$$$, $$$[1, 2, 1]$$$, $$$[2, 3]$$$, $$$[0, 1, 2]$$$.
The important key is in the locked box that you need to open. To open the box you need to enter secret code. Secret code is a permutation $$$p$$$ of length $$$n$$$.
You don't know this permutation, you only know the array $$$q$$$ of prefix maximums of this permutation. Formally:
You want to construct any possible suitable permutation (i.e. any such permutation, that calculated $$$q$$$ for this permutation is equal to the given array).
The first line contains integer number $$$t$$$ ($$$1 \le t \le 10^4$$$) — the number of test cases in the input. Then $$$t$$$ test cases follow.
The first line of a test case contains one integer $$$n$$$ $$$(1 \le n \le 10^{5})$$$ — the number of elements in the secret code permutation $$$p$$$.
The second line of a test case contains $$$n$$$ integers $$$q_1, q_2, \dots, q_n$$$ $$$(1 \le q_i \le n)$$$ — elements of the array $$$q$$$ for secret permutation. It is guaranteed that $$$q_i \le q_{i+1}$$$ for all $$$i$$$ ($$$1 \le i < n$$$).
The sum of all values $$$n$$$ over all the test cases in the input doesn't exceed $$$10^5$$$.
For each test case, print:
4 5 1 3 4 5 5 4 1 1 3 4 2 2 2 1 1
1 3 4 5 2 -1 2 1 1
In the first test case of the example answer $$$[1,3,4,5,2]$$$ is the only possible answer:
It can be proved that there are no answers for the second test case of the example.