/*
        Program Name: sample0.c
        written by  : Adnan El-Nasan
        Objective   : how to use getchar(), and putchar().
        Usage       : waits for an input from user.
                      if input = q or Q  -> quits;
                      if input in [0..9] -> '0..9' is printed out;
                      if input in [a..z] -> 'a..z' is printed out;
                      if input in [A..Z] -> 'A..Z' is printed out;
*/
              

#include <stdio.h>
#include <stdlib.h>

main()
{

int i,input;
while(1)                                /* forever */
 {
   input = getchar();                   /* read input key */
   if(input=='q') exit(1);              /* either quit or */

   if( (input>='0')&&(input<='9') )     /* print sequence */
   {
     for(i=48; i<58; i++)
       putchar(i);
     putchar('\n');                     /* CR/LF */
   }

   if( (input>='A')&&(input<='Z') )
   {
     for(i=65; i<91; i++)
       putchar(i);
     putchar('\n');
   }

   if( (input >='a')&&(input<='z') )
   {
     for(i=97; i<123; i++)
       putchar(i);
     putchar('\n');
   }

  }
}