A13331. String Modification
编程题
普及/提高-
知识点
题目描述
Vasya has a string $s$ of length $n$ . He decides to make the following modification to the string:
1. Pick an integer $k$ , ( $1 \leq k \leq n$ ).
2. For $i$ from $1$ to $n-k+1$ , reverse the substring $s[i:i+k-1]$ of $s$ . For example, if string $s$ is qwer and $k = 2$ , below is the series of transformations the string goes through:
- qwer (original string)
- wqer (after reversing the first substring of length $2$ )
- weqr (after reversing the second substring of length $2$ )
- werq (after reversing the last substring of length $2$ )
Hence, the resulting string after modifying $s$ with $k = 2$ is werq.
Vasya wants to choose a $k$ such that the string obtained after the above-mentioned modification is lexicographically smallest possible among all choices of $k$ . Among all such $k$ , he wants to choose the smallest one. Since he is busy attending Felicity 2020, he asks for your help.
A string $a$ is lexicographically smaller than a string $b$ if and only if one of the following holds:
- $a$ is a prefix of $b$ , but $a \ne b$ ;
- in the first position where $a$ and $b$ differ, the string $a$ has a letter that appears earlier in the alphabet than the corresponding letter in $b$ .
1. Pick an integer $k$ , ( $1 \leq k \leq n$ ).
2. For $i$ from $1$ to $n-k+1$ , reverse the substring $s[i:i+k-1]$ of $s$ . For example, if string $s$ is qwer and $k = 2$ , below is the series of transformations the string goes through:
- qwer (original string)
- wqer (after reversing the first substring of length $2$ )
- weqr (after reversing the second substring of length $2$ )
- werq (after reversing the last substring of length $2$ )
Hence, the resulting string after modifying $s$ with $k = 2$ is werq.
Vasya wants to choose a $k$ such that the string obtained after the above-mentioned modification is lexicographically smallest possible among all choices of $k$ . Among all such $k$ , he wants to choose the smallest one. Since he is busy attending Felicity 2020, he asks for your help.
A string $a$ is lexicographically smaller than a string $b$ if and only if one of the following holds:
- $a$ is a prefix of $b$ , but $a \ne b$ ;
- in the first position where $a$ and $b$ differ, the string $a$ has a letter that appears earlier in the alphabet than the corresponding letter in $b$ .
输入格式
Each test contains multiple test cases.
The first line contains the number of test cases $t$ ( $1 \le t \le 5000$ ). The description of the test cases follows.
The first line of each test case contains a single integer $n$ ( $1 \le n \le 5000$ ) — the length of the string $s$ .
The second line of each test case contains the string $s$ of $n$ lowercase latin letters.
It is guaranteed that the sum of $n$ over all test cases does not exceed $5000$ .
The first line contains the number of test cases $t$ ( $1 \le t \le 5000$ ). The description of the test cases follows.
The first line of each test case contains a single integer $n$ ( $1 \le n \le 5000$ ) — the length of the string $s$ .
The second line of each test case contains the string $s$ of $n$ lowercase latin letters.
It is guaranteed that the sum of $n$ over all test cases does not exceed $5000$ .
输出格式
For each testcase output two lines:
In the first line output the lexicographically smallest string $s'$ achievable after the above-mentioned modification.
In the second line output the appropriate value of $k$ ( $1 \leq k \leq n$ ) that you chose for performing the modification. If there are multiple values of $k$ that give the lexicographically smallest string, output the smallest value of $k$ among them.
In the first line output the lexicographically smallest string $s'$ achievable after the above-mentioned modification.
In the second line output the appropriate value of $k$ ( $1 \leq k \leq n$ ) that you chose for performing the modification. If there are multiple values of $k$ that give the lexicographically smallest string, output the smallest value of $k$ among them.
输入输出样例
输入 #1
6 4 abab 6 qwerty 5 aaaaa 6 alaska 9 lfpbavjsm 1 p
输出 #1
abab 1 ertyqw 3 aaaaa 1 aksala 6 avjsmbpfl 5 p 1
说明/提示
In the first testcase of the first sample, the string modification results for the sample abab are as follows :
- for $k = 1$ : abab
- for $k = 2$ : baba
- for $k = 3$ : abab
- for $k = 4$ : babaThe lexicographically smallest string achievable through modification is abab for $k = 1$ and $3$ . Smallest value of $k$ needed to achieve is hence $1$ .
- for $k = 1$ : abab
- for $k = 2$ : baba
- for $k = 3$ : abab
- for $k = 4$ : babaThe lexicographically smallest string achievable through modification is abab for $k = 1$ and $3$ . Smallest value of $k$ needed to achieve is hence $1$ .