Very Tough C Riddle

[Sam Kendall]

Is the token sequence

	[ ] [ ]

legal anywhere in a C program as defined in K&R?  If so, where and why?
If not, why not?

   Answers should be sent to me at

	{allegra,ihnp4,ima}!wjh12!talcott!kendall
     or	decvax!genrad!wjh12!talcott!kendall
     or	kendall%talcott at harvard.ARPA

Warning: some may consider the solution debatable, although I will
endeavor to prove them wrong, i.e., I am pretty sure I have the correct
answer.  I will summarize to the net.

	Sam Kendall