2009-2-18 The regular expression provided with the first programming assignment
has been corrected to also match 0. Here it is; the copy on the assignment specification has also been corrected.
/^[ \t]*((\-?[1-9][0-9]*)|0)([ \t]+((\-?[1-9][0-9]*)|0|[\+\-\*]))*[ \t]*$/