47.To check palliendrome




1.Using function

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

int main()
{
   char a[100], b[100];

   printf("Enter the string to check if it is a palindrome\n");
   gets(a);

   strcpy(b,a);
   strrev(b);

   if( strcmp(a,b) == 0 )
      printf("Entered string is a palindrome.\n");
   else
      printf("Entered string is not a palindrome.\n");

   return 0;
}


Method 2:

#include <stdio.h>

main()
{
   int n, reverse = 0, temp;

   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);

   temp = n;

   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }

   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);

   return 0;
}



Method 3: Without function

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

int main()
{
   char text[100];
   int begin, middle, end, length = 0;

   gets(text);

   while ( text[length] != '\0' )
      length++;

   end = length - 1;
   middle = length/2;

   for( begin = 0 ; begin < middle ; begin++ )
   {
      if ( text[begin] != text[end] )
      {
         printf("Not a palindrome.\n");
         break;
      }
      end--;
   }
   if( begin == middle )
      printf("Palindrome.\n");

   return 0;
}