Technocup 2020 - Elimination Round 3
B
Box
Codeforces
1200
原题
← AC →
翻译中…

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: $[0]$, $[1, 2, 1]$, $[2, 3]$, $[0, 1, 2]$.

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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 $n$.

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You don't know this permutation, you only know the array $q$ of prefix maximums of this permutation. Formally:

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  • $q_1=p_1$,
  • $q_2=\max(p_1, p_2)$,
  • $q_3=\max(p_1, p_2,p_3)$,
  • ...
  • $q_n=\max(p_1, p_2,\dots,p_n)$.
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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).

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Input

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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.

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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 $p$.

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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 $i$ ($1 \le i \lt n$).

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The sum of all values $n$ over all the test cases in the input doesn't exceed $10^5$.

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Output

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For each test case, print:

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  • If it's impossible to find such a permutation $p$, print "-1" (without quotes).
  • Otherwise, print $n$ distinct integers $p_1, p_2, \dots, p_n$ ($1 \le p_i \le n$). If there are multiple possible answers, you can print any of them.
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Note

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In the first test case of the example answer $[1,3,4,5,2]$ is the only possible answer:

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  • $q_{1} = p_{1} = 1$;
  • $q_{2} = \max(p_{1}, p_{2}) = 3$;
  • $q_{3} = \max(p_{1}, p_{2}, p_{3}) = 4$;
  • $q_{4} = \max(p_{1}, p_{2}, p_{3}, p_{4}) = 5$;
  • $q_{5} = \max(p_{1}, p_{2}, p_{3}, p_{4}, p_{5}) = 5$.
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It can be proved that there are no answers for the second test case of the example.

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样例

Input #1
4
5
1 3 4 5 5
4
1 1 3 4
2
2 2
1
1
Output #1
1 3 4 5 2
-1
2 1
1
InputCopy OutputCopy
题目信息
题号
1227B
时间限制
1 s
内存限制
256 MB
标签
构造

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。