Kerst's challenge script

alias maths { 
set %y $calc( $numtok($3-,32) - 2) 
set %d $calc($3-$ [ $+ [ %y ] ] ) 
/echo -a $3-$ [ $+ [ %y ] ] = %do $+, $ [ $+ [ $numtok($1-,32) ] ] - %d = $1 
/echo -a $1 = $calc( $ [ $+ [ $numtok($1-,32) ] ] - %d ) 
}