palindrome function

[Unregistered]

ok here is how i figure i would do it...

get input
determine lenght of string and reverse it bu looping a decreasing for loop and concatenating the strings into a second string
eg: text[100] added to reversedstring then text[99] added to reverstring and so on...

then i would use the strcmp function to test for equality and see if it is indeed a palindrome... is this the best way to do it? anyone else have some faster or better pseusocode also i dont know how to determine the lenght of a string

[ihsir]

use strlen(string) for length
strcmp(str1,str2) for cmp

yeah its fast but more mem will be used

or you could use 2 loops one from 0 and incrementing and the other one from 99 and decrementing; comparing 0-99, 1-98 so on to see for palindrome.

[Prelude]

This has been handled many times before, just click on this to see.

-Prelude

[Unregistered]

ok no i have a litle problem the uncommented lines i do not understand... what does tolower do?

char* start = text; //pass the whole array into the start variable
   char* end = text + strlen(text) - 1; //pass the last charecter of the array into end
   while(end > start)
   {
       if(tolower(*start) != tolower(*end))
       {
           return(0);
       }
       end--;
       start++;
   }
   return(1);

[Prelude]

tolower will return the upper case equivalent of the character that you pass to it.

-Prelude