307731: CF1405A. Permutation Forgery

Memory Limit:256 MB Time Limit:1 S
Judge Style:Text Compare Creator:
Submit:0 Solved:0

Description

Permutation Forgery

题意翻译

对于一个长度为 $n$ 的排列 $p$,定义其 **fingerprint** $F(p)$ 为 $p$ 中相邻元素和排序后得到的数组。更形式化地, $$F(p)=\text{sort}([p_1+p_2,p_2+p_3,\cdots,p_{n-1}+p_n])$$ 比如 $n=4$,$p=[1,4,2,3]$,则 $F(p)=\text{sort}([1+4,4+2,2+3])=\text{sort}([5,6,5])=[5,5,6]$。 给定一个长度为 $n$ 的排列 $p$,你需要找到一个与 $p$ 不同但 fingerprint 相同的排列 $p'$。

题目描述

A permutation of length $ n $ is an array consisting of $ n $ distinct integers from $ 1 $ to $ n $ in arbitrary order. For example, $ [2,3,1,5,4] $ is a permutation, but $ [1,2,2] $ is not a permutation ( $ 2 $ appears twice in the array) and $ [1,3,4] $ is also not a permutation ( $ n=3 $ but there is $ 4 $ in the array). Let $ p $ be any permutation of length $ n $ . We define the fingerprint $ F(p) $ of $ p $ as the sorted array of sums of adjacent elements in $ p $ . More formally, $ $F(p)=\mathrm{sort}([p_1+p_2,p_2+p_3,\ldots,p_{n-1}+p_n]). $ $ </p><p>For example, if $ n=4 $ and $ p=\[1,4,2,3\], $ then the fingerprint is given by $ F(p)=\\mathrm{sort}(\[1+4,4+2,2+3\])=\\mathrm{sort}(\[5,6,5\])=\[5,5,6\] $ .</p><p>You are given a permutation $ p $ of length $ n $ . Your task is to find a <span class="tex-font-style-bf">different</span> permutation $ p' $ with the same fingerprint. Two permutations $ p $ and $ p' $ are considered different if there is some index $ i $ such that $ p\_i \\ne p'\_i$.

输入输出格式

输入格式


Each test contains multiple test cases. The first line contains the number of test cases $ t $ ( $ 1 \le t \le 668 $ ). Description of the test cases follows. The first line of each test case contains a single integer $ n $ ( $ 2\le n\le 100 $ ) — the length of the permutation. The second line of each test case contains $ n $ integers $ p_1,\ldots,p_n $ ( $ 1\le p_i\le n $ ). It is guaranteed that $ p $ is a permutation.

输出格式


For each test case, output $ n $ integers $ p'_1,\ldots, p'_n $ — a permutation such that $ p'\ne p $ and $ F(p')=F(p) $ . We can prove that for every permutation satisfying the input constraints, a solution exists. If there are multiple solutions, you may output any.

输入输出样例

输入样例 #1

3
2
1 2
6
2 1 6 5 4 3
5
2 4 3 1 5

输出样例 #1

2 1
1 2 5 6 3 4
3 1 5 2 4

说明

In the first test case, $ F(p)=\mathrm{sort}([1+2])=[3] $ . And $ F(p')=\mathrm{sort}([2+1])=[3] $ . In the second test case, $ F(p)=\mathrm{sort}([2+1,1+6,6+5,5+4,4+3])=\mathrm{sort}([3,7,11,9,7])=[3,7,7,9,11] $ . And $ F(p')=\mathrm{sort}([1+2,2+5,5+6,6+3,3+4])=\mathrm{sort}([3,7,11,9,7])=[3,7,7,9,11] $ . In the third test case, $ F(p)=\mathrm{sort}([2+4,4+3,3+1,1+5])=\mathrm{sort}([6,7,4,6])=[4,6,6,7] $ . And $ F(p')=\mathrm{sort}([3+1,1+5,5+2,2+4])=\mathrm{sort}([4,6,7,6])=[4,6,6,7] $ .

Input

题意翻译

对于一个长度为 $n$ 的排列 $p$,定义其 **fingerprint** $F(p)$ 为 $p$ 中相邻元素和排序后得到的数组。更形式化地, $$F(p)=\text{sort}([p_1+p_2,p_2+p_3,\cdots,p_{n-1}+p_n])$$ 比如 $n=4$,$p=[1,4,2,3]$,则 $F(p)=\text{sort}([1+4,4+2,2+3])=\text{sort}([5,6,5])=[5,5,6]$。 给定一个长度为 $n$ 的排列 $p$,你需要找到一个与 $p$ 不同但 fingerprint 相同的排列 $p'$。

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