题解 | #字符串排序#

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#define max 30000
#define row 1001
#define col 1001

int is_upper(char a)
{
   return((a >= 'A') && (a <= 'Z'));
}

int is_lower(char a)
{
   return((a >= 'a') && (a <= 'z'));
}

char to_upper(char a)
{
   if (is_lower(a))
   {
      return a - ('a' - 'A');
   }
   else
   {
      return a;
   }
}

char tolower(char a)
{
   if (is_upper(a))
   {
      return a + ('a' - 'A');
   }
   else
   {
      return a;
   }
}

int char_cmp(char a, char b)
{
   return(a - b);
}


int main()
{
   char s[max];
   char d[max];
   int i = 0, j = 0, k = 0, m = 0, n = 0;
   char a, b, c;

   while (gets(s) != NULL)
   {
      m = strlen(s);
      strcpy(d, s);

      for (i = 0, j = 0; s[i] != '\0'; i++)
      {
         if (is_upper(s[i]) || is_lower(s[i]))//skip illegal character
         {
            s[j++] = s[i];
            d[i] = -1;
         }
      }
      s[j] = 0;

      for (i = 0, m = 0; s[i] != '\0'; i++)
      {
         for (j = i + 1, k = i; s[j] != '\0'; j++)
         {
            if (is_upper(s[j]))
            {
               if (char_cmp(s[j], to_upper(s[k])) < 0)
               {
                  k = j;
               }
            }
            else if (is_lower(s[j]))
            {
               if (char_cmp(s[j], tolower(s[k])) < 0)
               {
                  k = j;
               }
            }
            else
            {

            }
         }

         if (k > i)
         {
            a = s[k];

            for (j = k; j > i; j--)
            {
               s[j] = s[j - 1];
            }

            s[i] = a;
         }
      }

      for (i = 0, j = 0; d[i] != '\0'; i++)
      {
         if (d[i] == -1)
         {
            d[i] = s[j++];
         }
      }

      puts(d);
   }

   return 0;
}