Amhuxt.420
net.games.trivia
utzoo!decvax!harpo!eagle!mhuxt!presley
Mon Apr 19 16:18:03 1982
Parametrivia
Here's a nice and easy quiz for those of you who miss those
compiler courses you took in school.  It's from the Gries
book "Compiler Construction for Digital Computers".
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Consider the ALGOL-like program:
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	BEGIN INTEGER I; INTEGER ARRAY B[1,2];
		PROCEDURE Q(X); INTEGER X;
		BEGIN I := 1; X := X + 2; B[I] := 10;
		      I := 2; X := X + 2;
		END;
	  B[1] := 1; B[2] := 1; I := 1; Q(B[I]);
	END;
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Tell what the final values for B[1] and B[2] are, assuming the
formal parameter X to be: (1) called by reference, (2) called by
value, (3) called by value result, (4) called by result, and
(5) called by name.
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Have fun!  Answers in about a week or so.
	Joe Presley