C Programming

Program 65) Write a program that uses a table of integers whose size will be specified interactively at run time.

The program is shown below. It tests for avaibility of memory space of required size. If it is available, then the required space is allocated and the address of the first byte of the space allocated is displayed. The program also illustrates the use of pointer varaible for storing and accessing the table values.

                                      PROGRAM

#include <stdio.h>
#include <stdlib.h>
#define NULL 0

main ( )
 {
       int *p, *table ;
       int size ;
       printf ("\nWhat is the size of table?") ;
       scanf("%d", size) ;
       printf ("\n") ;
          /* - - - - - -Memory allocation - - - - - - */
       if ((table = (int*) malloc (size *sizeof (int))) == NULL)
         {
             printf ("No space available \n") ;
             exit (1) ;
         }
      printf ("\n Address of the first byte is %u\n", table) ;
         /*   Reading table values   */
      printf ("\nInput table values\n") ;

     for (p = table; p < table + size; p++)
           scanf (%d", p) ;
    /*        Printing table value in reverse order   */
    for (p = table + size -1; p >= table; p --)
           printf ("%d is stored at address %u \n", *p,p) ;

 }

Output:             What is the size of the table? 5
                         Address of teh first byte is 2262
                         Input table values
                         11  12  13  14  15
                         15  is stored at address 2270
                         14 is stored at address 2268
                         13 is stored at address 2266
                         12 is storedat address 2264
                         11 is stored at address 2262