CSC 3101 SPU Semantic Function in Denotational Semantics Questions

. P A U L ’S
S T
UN
ST. PAUL’S UNIVERSITY
I VE R S I TY
SE R
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VANT
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SCHOOL OF COMMUNICATION AND COMPUTER STUDIES
UNIVERSITY EXAMINATIONS
MAY – AUGUST 2023/2024 SEMESTER
BACHELOR OF SCIENCE IN COMPUTER SCIENCE
UNIT CODE: CSC 3101
UNIT TITLE: PRINCIPLES OF PROGRAMMING LANGUAGES
DATE: AUGUST, 2023
TIME: 2 Hours
INSTRUCTIONS:
1. Answers ALL Questions.
2. Submit your answers in word format unless otherwise instructed. Type your
answers in a word document. Do not PDF your document.
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NOTE: Submission deadlines must be observed.
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instructions:
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Write your student number in full
Write the unit code and title
Write the date of examination
− Write “SUPPLEMENTARY” or “DEFFERED EXAM” as the case may be, (if
you are taking a supplementary or deferred examination).
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QUESTION ONE (15 MARKS)
a) Using proof tree in operational Semantics, Show that
-(*(/(8,4), 2), 2) evaluates to 2
(6 Marks)
b) In denotational Semantics, Semantic Function(M) is represented as:
M: B → N where N is a set of Natural numbers including 0 and B is the domain string of
binary numbers.
Using the five rules of Denotational Semantics for binary addition, show that:
M[[010 1100 ⊕ 001 0110]] = 66 = M[[100 0010]]. NB: show ALL steps.
(9 marks)
QUESTION TWO (15 MARKS)
a) Given a CFG below, use bottoms up parsing to parse the string “abbcbcbcde” (6 marks)
S → aABe
A → Abc | b
B→d
b) Show the three-address code for the expression “x:= y*-z + y/z ” and indicate all the
temporary variables.
(4 marks)
c) Represent the following expression “a*b + d/c”
i) Using AST
(3 Marks)
ii) Using a parse tree.
(2 Marks)
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