#include <stdio.h>
#include <string.h>
 
copylen(char *a);
char reverse(char *s, char *t);


int main()

{

     char source[25];							/* source string */

     char target[25];							/* Target string */

    printf("Enter the source string\n");

     scanf("%s", source);
     
     /* function which passes the base address of source and target */
     reverse(source, target);
     
     printf("The target string is %s", target);
     
     getch();
 
}
 
 
 
char reverse(char *s, char *t)			/* Pointers to source and target */

{
 
      int length=0;		
      /* The length of the source string is calculated and then assigned to length using copylen*/
      length=copylen(s)-1;	
      
      while(length>=0)	
      {
       /* the last charachter s[length] or *(s+length) is copied to the target */
          *t=*(s+length);
       
      /* The pointer is made to point to the next memory address of the target */
          t++;
       
      /* length is reduced so the the next charachter is s[length-1] */
      length--;
      }
      *t='\0';		   /* The terminating charchter is assigned to the end of the target */	
} 
      
copylen(char *a)
{
  int len=0;  /* Initialize length variable */
  
  while(*a!='\0')  /* Till termination charachter is met continue the loop */
  {
     len++;      /* Increase length */
     a++;        /* shift the pointer to the next location */
  }
  return len;   /* The length which will be the length of the string */
}