#  While20.py  (c) 1997-2006 Kari Laitinen

#  http://www.naturalprogramming.com

#  2006-04-18  File created.
#  2006-05-30  Last modification.

#  The 'print' command in Python is a statement, i.e.,
#  'print' is a reserved keyword.

#  The print statement prints a newline after each 
#  printing operation unless there is a comma at the end
#  of the print statement. The print statement adds a
#  space character after each printed item.

#  The while loops in Python programs are logically similar to
#  the while loops in Java/C++/C# languages.
#  The internal statements of the loop must be indented.

print  "\nNumbers from 0 to 20 are the following:\n"

number_to_print  =  0

while  number_to_print  <=  20  :

   print "%d"  %  number_to_print,
   number_to_print  +=  1


#  The print statement inside the above loop could alternatively
#  be written in the following way.

#   print number_to_print,