B - Palindromes
Time Limit:3000MS Memory Limit:0KB 64bit IO Format:%lld & %llu
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Description
A regular palindrome is a string of numbers or letters that is the same forward as backward. For example, the string "ABCDEDCBA" is a palindrome because it is the same when the string is read from left to right as when the string is read from right to left.
A mirrored string is a string for which when each of the elements of the string is changed to its reverse (if it has a reverse) and the string is read backwards the result is the same as the original string. For example, the string "3AIAE" is a mirrored string because "A" and "I"are their own reverses, and "3" and "E" are each others' reverses. A mirrored palindrome is a string that meets the criteria of a regular palindrome and the criteria of a mirrored string. The string"ATOYOTA" is a mirrored palindrome because if the string is read backwards, the string is the same as the original and because if each of the characters is replaced by its reverse and the result is read backwards, the result is the same as the original string.
Of course,"A","T", "O", and "Y" are all their own reverses.
A list of all valid characters and their reverses is as follows.
| Character | Reverse | Character | Reverse | Character | Reverse |
| A | A | M | M | Y | Y |
| B |
| N |
| Z | 5 |
| C |
| O | O | 1 | 1 |
| D |
| P |
| 2 | S |
| E | 3 | Q |
| 3 | E |
| F |
| R |
| 4 |
|
| G |
| S | 2 | 5 | Z |
| H | H | T | T | 6 |
|
| I | I | U | U | 7 |
|
| J | L | V | V | 8 | 8 |
| K |
| W | W | 9 |
|
| L | J | X | X |
|
|
Input
Input consists of strings (one per line) each of which will consist of one to twenty valid characters. There will be no invalid characters in any of the strings. Your program should read to the end of file.
Output
For each input string, you should print the string starting in column 1 immediately followed by exactly one of the following strings.
| STRING | CRITERIA |
| " -- is not a palindrome." | if the string is not a palindrome and is not a mirrored string |
| " -- is a regular palindrome." | if the string is a palindrome and is not a mirrored string |
| " -- is a mirrored string." | if the string is not a palindrome and is a mirrored string |
| " -- is a mirrored palindrome." | if the string is a palindrome and is a mirrored string |
Note that the output line is to include the -'s and spacing exactly as shown in the table above and demonstrated in the Sample Output below.
In addition, after each output line, you must print an empty line.
Sample Input
NOTAPALINDROME
ISAPALINILAPASI
2A3MEAS
ATOYOTA
Sample Output
NOTAPALINDROME -- is not a palindrome.
ISAPALINILAPASI -- is a regular palindrome.
2A3MEAS -- is a mirrored string.
ATOYOTA -- is a mirrored palindrome.
Hint
use the C++'s class of string will be convenient, but not a must
题意：
Palindrome表示一个字符串是“回文串”。Mirroed string 代表将一个字符串中的所有字符左右翻转后形成新字符串，再由后向前读取，结果与原来字符串相同。需要判断输入字符串是什么类型的。
输入：
多组数据，每组为不超过20个字符的字符串。
输出：
每组数据输出其字符串的类型。共四种：非镜像非回文、镜像、回文、镜像回文。
分析：
就是简单进行模拟就好。判断回文串的函数好写，注意在写判断镜像串的时候需要先宏定义一个数组存储题目表格中的每个字符所对应的镜像字符（字母和数字分别存储，方便查找），如果该字符没有镜像字符，那么它所对应的镜像字符置为空格。
1 #include2 #include 3 #include 4 using namespace std; 5 char MirroredChar[] = { 'A',' ',' ',' ','3',' ',' ','H','I','L',' ','J','M',' ','O',' ',' ',' ','2','T','U','V','W','X','Y','5'}; 6 char MirroredNum[] = { '1','S','E',' ','Z',' ',' ','8',' '}; 7 bool IsPalindromes(char str[]){ 8 int len = strlen(str); 9 for(int i = 0,j = len - 1 ; i < j ; i++,j--)10 if(str[i] != str[j]) return false;11 return true;12 }13 bool IsMirrored(char str[]){14 int len = strlen(str);15 char tmp;16 for(int i = 0,j = len - 1 ; i < len ; i++,j--){17 if(str[i] >= 'A' && str[i] <= 'Z')18 tmp = MirroredChar[str[i] - 'A'];19 else20 tmp = MirroredNum[str[i] - '1'];21 if(tmp != str[j]) return false;22 }23 return true;24 }25 int main(){26 char str[1000];27 while(scanf("%s",str) != EOF){28 printf("%s -- ",str);29 bool k1 = IsPalindromes(str);30 bool k2 = IsMirrored(str);31 if(!k1 && !k2) printf("is not a palindrome.\n");32 else if(k1 && k2) printf("is a mirrored palindrome.\n");33 else if(k1 && !k2) printf("is a regular palindrome.\n");34 else printf("is a mirrored string.\n");35 cout << endl;36 }37 return 0;38 }