#
# Regular Definitions
#
rl rl_ws /[ \t\n\r\v]+/
rl rl_id /[a-zA-Z_][a-zA-Z0-9_]*/

#
# Tokens
#

lex start
{
	ignore /rl_ws/
	token id /rl_id/
}

global num: int
global allow: int = 3

def item 
	[id]
	{
		num = num + 1
		toomuch: int = allow+1
		if num == toomuch {
			reject
		}
	}

def open
	[]
	{
		num = 0
	}

def close []

def restricted_list 
	[open item*]

def start 
	[restricted_list id*]

print_xml( parse start(stdin) )