UVA401（回文子串和镜像串）

Posted 2020-06-11

可以先设一个常量镜像串，直接返回比较

#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <stack>
#include <cctype>
using namespace std;

#define mem(a,b) memset(a,b,sizeof(a))
#define pf printf
#define sf scanf
#define spf sprintf
#define debug printf("!\n")
#define INF 10000
#define MAXN 5010
#define MAX(a,b) a>b?a:b
#define blank pf("\n")
#define LL long long

const char* rev = "A   3  HIL JM O   2TUVWXY51SE Z  8 ";
const char* msg[]={"is not a palindrome.","is a regular palindrome.","is a mirrored string.","is a mirrored palindrome."};

char str[MAXN];

char change(char ch)
{
     if(isalpha(ch)) return rev[ch-‘A‘];
     return rev[ch-‘0‘+25];
}

int main()
{
     while(~sf("%s",str))
     {
          int p=1,m=1,i;
          int len = strlen(str);
          for(i=0;i<(len+1)/2;i++)
          {
               if(str[i]!=str[len-i-1]) p=0;
               if(change(str[i])!=str[len-i-1]) m=0;
          }
          pf("p:%d m:%d\n",p,m);
          pf("%s -- is %s\n",str,msg[p+m*2]);
     }
}
/*
NOTAPALINDROME
ISAPALINILAPASI
2A3MEAS
ATOYOTA
*/