Philadelphia University
Faculty of Information Technology
Lecturer
: Dr. M. Maouche
Coordinator
: Dr M. Maouche
Internal Examiner : Dr. N. Nameer
Department of Computer Science
Examination Paper
Course Name: Compiler Construction (750324)
Section: 1
Second Exam
First Semester
Academic Year: 2015/16
Date: December, 31th, 2015
Time: 50 minutes
Information for Candidates
1.This examination paper contains 4 questions, totaling 20 marks.
2.The marks for parts of questions are shown in round brackets.
Advice to Candidates
1. You should write your answers precisely, clearly and to the point .
I. Basic Notions
Objectives. The aim of the question in this part is to evaluate the required minimal student
knowledge and skills. Answers in the pass category represent the minimum acceptable
standard.
Question1: (6 marks)
Answer the following MCQ questions
1. Shift Reduce parsers are:
A. Top Down parsers
B. Bottom parsers
C. May be top down or bottom up parsers
D. None of the above.
2. A top down parser generates
A. Right Most Derivation
B. Left Most Derivation
C. Right Most Derivation in Reverse
D. Left Most Derivation in Reverse
3. LR stands for
A. Left to Right
B. Left to Right Reduction
C. Right to left
D. Left to right and right most derivation in reverse
4. Recursive descent parsing is an example
A. Top down parsing
B. Bottom parsing
C. Backtracking parsing
D. Reduce Shift parsing
5. What is a sentential form?
A. One line of a derivation
B. An arbitrary string of grammar symbols
C. The content of the LL(1) parse stack
D. The string of symbols between the current point in the parse and the root of the parse tree
6. Which of the following is concerned by semantic analysis
A. Uniqueness checks
B. Type checks
C. Flow of control checks
D. All of the above
II. Familiar Problems Solving
Objectives. The aim of the question in this part is to evaluate that the student has some basic
knowledge of the key aspects of the lecture material and can attempt to solve familiar
problems
Question2: (6 marks)
Given the following grammar:
SA
S B
A  cA + b
Aa
B  cB + a
Bb
S, A, B are non terminals; a, b, c and + are terminals
Compute: First (S) = {
} (3 marks) ; Followers (B) = { } (3 marks)
Explain each step of the computations.
Question3: (5 marks)
Given the following grammar:
E  (E + E)
Ex
E is a start non terminal
x, (, ), and + are terminals.
1. Compute the state S0 of the FSA obtained by applying the reduce shit parsing
technique. (2 marks)
2. Compute: Goto (S0, E) and Goto (S0, ()
(3 marks)
Explain each step of your computations.
III. Unfamiliar Problems Solving
Objectives. The aim of the question in this part is to evaluate that the student has some basic
knowledge of the key aspects of the lecture material and can attempt to solve unfamiliar
problems.
Question4: (3 marks)
Construct a recursive-descent parser for the following grammar:
S -> + S S | - S S | a
Assume that the match function is available.