307731: CF1405A. Permutation Forgery
Memory Limit:256 MB
Time Limit:1 S
Judge Style:Text Compare
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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