c program for palindrome

C program for palindrome

#include <stdio.h>

#include <string.h>

#include<conio.h> 

void main()

{

   char a[100], b[100];

   clrscr();

   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");

   getch();

}

Output of program:

Palindrome number in c

#include <stdio.h>

#include<conio.h> 

void main()

{

   int n, reverse = 0, temp;

   clrscr();

   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);

   getch();

}

C program for palindrome without using string functions

#include <stdio.h>

#include <string.h>

#include<conio.h> 

void main()

{

   char text[100];

   int begin, middle, end, length = 0;

   clrscr();

   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");

   getch();

}

C program check palindrome

#include <stdio.h>

#include<conio.h> 

int is_palindrome(char*);

void copy_string(char*, char*);

void reverse_string(char*);

int string_length(char*);

int compare_string(char*, char*);

void main()

{

   char string[100];

   int result;

   clrscr();

   printf("Enter a string\n");

   gets(string);

   result = is_palindrome(string);

   if ( result == 1 )

   printf("\"%s\" is a palindrome string.\n", string);

   else

   printf("\"%s\" is not a palindrome string.\n", string); 

   getch();

}

int is_palindrome(char *string)

{

   int check, length;

   char *reverse;

   length = string_length(string);    

   reverse = (char*)malloc(length+1);    

   copy_string(reverse, string);

   reverse_string(reverse);

   check = compare_string(string, reverse);

   free(reverse);

   if ( check == 0 )

   return 1;

   else

   return 0;

}

int string_length(char *string)

{

   int length = 0;  

   while(*string)

   {

      length++;

      string++;

   }

   return length;

}

void copy_string(char *target, char *source)

{

   while(*source)

   {

      *target = *source;

      source++;

      target++;

   }

   *target = '\0';

}

void reverse_string(char *string) 

{

   int length, c;

   char *begin, *end, temp;

   length = string_length(string);

   begin = string;

   end = string;

   for ( c = 0 ; c < ( length - 1 ) ; c++ )

   end++;

    for ( c = 0 ; c < length/2 ; c++ ) 

   {        

      temp = *end;

      *end = *begin;

      *begin = temp;

      begin++;

      end--;

   }

}

int compare_string(char *first, char *second)

{

   while(*first==*second)

   {

      if ( *first == '\0' || *second == '\0' )

         break;

      first++;

      second++;

   }

   if( *first == '\0' && *second == '\0' )

      return 0;

   else

      return -1;

}