WAP function using a pointer to a function

/*WAP Invoking a function using a pointer to a function */

#include<stdio.h>
#include<conio.h>
main( )
{
 int  display( ) ;
 int  ( *func_ptr )( ) ;

 func_ptr = display ;  /* assign address of function */ 
 printf ( "\nAddress of function display is %u", func_ptr ) ;
 ( *func_ptr )( ) ;  /* invokes the function display( ) */
         getch();
}

int  display( )
{
 puts ( "\nLong live viruses!!" ) ;
}

WAP to Using pointer to access array elements

/*WAP to Using pointer to access array elements */

#include<stdio.h>
#include<conio.h>
main( )
{
 char  name[ ] = "Goldfish" ;
 char  *ptr ;

 ptr = name ;  /* store base address of string */

 while ( *ptr != `\0' )
 {
  printf ( "%c", *ptr ) ;
  ptr++ ;
 }
}

WAP to Usage of pointer to an array

/*WAP to Usage of pointer to an array */

#include<stdio.h>
#include<conio.h>
main( )
{
 int  s[5][2] = {
     { 1234, 56 },
     { 1212, 33 },
     { 1434, 80 },
     { 1312, 78 }
       } ;  
 int  ( *p )[2] ;
 int  i, j, *pint ;
 
 for ( i = 0 ; i <= 3 ; i++ )
 {
   p = &s[i] ;
  pint = p ;
  printf ( "\n" ) ;
  for ( j = 0 ; j <= 1 ; j++ )
   printf ( "%d ", *( pint + j ) ) ; 
 }
}

WAP to access array elements

/*WAP to access array elements */

#include<stdio.h>
#include<conio.h>
main( )
{
 int  num[ ] = { 24, 34, 12, 44, 56, 17 } ;
 int  i ;

 for ( i = 0 ; i <= 5 ; i++ )
 {
  printf ( "\naddress = %u ", &num[i] ) ;
  printf ( "element = %d", num[i] ) ;
 }
}

WAP to print out the memory locations

/*WAP to print out the memory locations*/

#include<stdio.h>
#include<conio.h>
main( )
{
 int  num[ ] = { 24, 34, 12, 44, 56, 17 } ;
 int  i ;

 for ( i = 0 ; i <= 5 ; i++ )
 {
  printf ( "\nelement no. %d ", i ) ;
  printf ( "address = %u", &num[i] ) ;
 }
}

WAP to Comparison of two pointer variables

/*WAP to Comparison of two pointer variables */

#include<stdio.h>
#include<conio.h>
main( )
{
 int  arr[ ] = { 10, 20, 36, 72, 45, 36 } ;
 int  *j, *k ;

 j = &arr [ 4 ] ;
 k = ( arr + 4 ) ;

 if ( j == k )
  printf ( "The two pointers point to the same location" ) ;
 else
  printf ( "The two pointers do not point to the same location" ) ;
}

WAP to Subtraction of one pointer from another

/*WAP to Subtraction of one pointer from another*/

#include<stdio.h>
#include<conio.h>
main( )
{
 int  arr[ ] = { 10, 20, 30, 45, 67, 56, 74 } ;
 int  *i, *j ;

 i = &arr[1] ;
 j = &arr[5] ;
 printf ( "%d %d", j - i, *j - *i ) ;
}

WAP to Introducing pointers

/*WAP to Introducing pointers */

#include<stdio.h>
#include<conio.h>
main( )
{
 int  i = 3, *x ;
 float  j = 1.5, *y ;
 char  k = 'c', *z ;

 printf ( "\nValue of i = %d", i ) ;
 printf ( "\nValue of j = %f", j ) ;
 printf ( "\nValue of k = %c", k ) ;
 x = &i ;
 y = &j ;
 z = &k ;
 printf ( "\nOriginal address in x = %u", x ) ;
 printf ( "\nOriginal address in y = %u", y ) ;
 printf ( "\nOriginal address in z = %u", z ) ;
 x++ ;
 y++ ;
 z++ ;
 printf ( "\nNew address in x = %u", x ) ;
 printf ( "\nNew address in y = %u", y ) ;
 printf ( "\nNew address in z = %u", z ) ;
}