#! /bin/sh

: 'This file is in the public domain, so clarified as of'
: '2006-07-17 by Arthur David Olson.'

match $Argc-$1 {
	with 2-|2-0*|2-*[!0-9]*
		echo "$0: wild year: $1" > !2
		exit 1 
}

match $Argc-$2 {
	with 2-even
		match $1 {
			with *[24680]			exit 0 
			with *				exit 1 
		} 
	with 2-nonpres|2-nonuspres
		match $1 {
			with *[02468][048]|*[13579][26]	exit 1 
			with *				exit 0 
		} 
	with 2-odd
		match $1 {
			with *[13579]			exit 0 
			with *				exit 1 
		} 
	with 2-uspres
		match $1 {
			with *[02468][048]|*[13579][26]	exit 0 
			with *				exit 1 
		} 
	with 2-*
		echo "$0: wild type: $2" > !2 
}

echo "$0: usage is $0 year even|odd|uspres|nonpres|nonuspres" > !2
exit 1