Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Computer Engineering Expert

problem 1: Given the production:

S-> aSAb | Ab
A-> bbb
implement a complete pseudo code for a recursive descent parser. Assume scanner ( ) returns the next token.

problem 2: Give all needed first and follow sets needed to check if the grammar is LL(1). Is it?:

S -> aA | BB
A -> aaA | empty
B -> bB | Cd
C -> cA | dC

problem 3: A function returns a number, takes no arguments, and its body is a block. Functions are defined exactly like variables in the grammar except that function name is follow by a block. Show the grammar. Is the resulting grammar LL(1)?

problem 4: A function definition must be before the program token, and functions cannot be nested (exactly like in C). Every function has a return type (no void) and one argument. Function call is like in C, with an expression for the argument and the function call itself is an expression. Show the grammar. exs:

int fun1(long x)
begin
/* same as in any block*/
end;
long fun2(int x)
begin
/** ... */
end;
program xxx(void)
begin
int x;
x=fun1(5+2)*10;
end;

problem 5: Design unambiguous grammar to parse expressions involving +, -, *, / and unary -. Unary minus is strongest, followed by * and /(same precedence, right associative), then +, left associative, then finally -, left associative. Do not use any other operators, and use only number tokens.

problem 6: Assume function f ( ) has local variables a, b, and function g is nested inside of f ( ) and has local variable a. There is also a global variable c.

a) show the complete memory space for the program when it begins execution
b) show the stack after f ( ) is called, which subsequently calls g ( ), which calls itself once.
c) assume we have three statements in g ( )

stat1: c=10;
stat2: a=20;
stat3: b=30;
how would they be translated by the compiler: describe in words.

problem 7: Show the grammar for:

a) Allow global variables placed just before the first begin – these variables are optional and are listed separated by commas. For ex:

program
int x,y,z;
begin {etc.}

b) Also allow functions. Each function takes any number of arguments and always returns an integer. Parameter list is C-like, and the return statement (followed by an expression) is mandatory. Functions can be called in place of any expression. Functions are defined with a block, which is the same as the begin-end block in our grammar. Functions are defined separately, as in C but before the main program. Assume we have a multi-pass compiler so that prototypes is not an issue. The following is an ex program

int sum(int a, b) {paramater list is same as for globals}
begin
int c;
return a+b;
end;
program
int x,y;
begin
readI(x);
readI(y);
z:=10+sum(x,y+1);
prepareI(z);
end.

problem 8: Given the program (like Pascal, with nested functions)

int x, y; {global}
function A
begin
int z; {z is in A}
function B {B is defined inside A}
begin
int x; {x is in B}
function C {C is inside B}
begin
int x; {x is in C}
z:=10:
x:=100;
y:=1000;
C(); {recursive call on C}
end; {end of C}
C();
end; {end of B}
B(); { A calls B}
end; {end of A}

a) show ARs (activation Records) for A, B, C (show only local data, static and dynamic link}
b) What is in the persistent data space?
c) assume call to A() is done somewhere. Then, show that contents of the stack during the 3rd recursive call to C(). Make sure to fill out all info on the stack.
d) How would the left-hand-side variables in C()be translated by the compiler (describe in words, separately for each variable).

problem 9: Given the grammar, with lower case terminals and upper case nonterminals, and S the initial nonterminal

S -> aS | aA | bA
A -> Aa | ABb | cA
B -> bB | bdB | c

a) remove left recursion as needed, showing the modified grammar

b) left-factorize as needed what you get in a), showing the new grammar

c) Is the resulting grammar LL(1)? Argue piece by piece why it is or why it is not, showing all (and only the necessary) First and Follow sets.

problem 10: Assume the following static program structure, show the static chains and display when exactly five ARs are on the stack, assuming procedure A is called first.

proc A
begin /* proc A */
proc B
begin /* proc B */
proc C
begin /* proc C */
call A
end /* proc C */
call C
end /* proc B */
proc D
begin /* proc D */
call B
end /* proc D */
call D
end /* proc A */

Computer Engineering, Engineering

  • Category:- Computer Engineering
  • Reference No.:- M93892

Have any Question? 


Related Questions in Computer Engineering

What is the relationship between increased social

What is the relationship between increased social responsibility and IT at the workplace? Answer in about two paragraphs with reference. Must be 200-400 words and show an understanding and full development of the concept ...

1 what is an architectural style2 what is a design pattern3

1. What is an architectural style? 2. What is a design pattern? 3. Explain the principle of separation of concerns, and the advantages it entails for software development. 4. What is the purpose of each component in a mo ...

1 run the binary search method on a set of unordered data

1. Run the binary search method on a set of unordered data. What happens? 2. Using the CArray class with the SeqSearch method and the BinSearch method, create an array of 1,000 random integers. Add a new private Integer ...

1 in your own words describe the two motivations for

1. In your own words, describe the two motivations for defining functions in your programs. 2. We have been thinking about computer programs as sequences of instructions where the computer methodically executes one instr ...

Writenbspa java program non-gui preferred to demonstrate

Write  a Java program (non-GUI preferred) to demonstrate the use of JDBC. The program should allow a user to do the following: Write a list of animal and its characteristics to a database using JDBC Display the character ...

Implement a votingmachine class that can be used for a

Implement a VotingMachine class that can be used for a simple election. Have methods to clear the machine state, to vote for a Democrat, to vote for a Republican, and to get the tallies for both parties. Extra credit if ...

Why are system safety principles not used by all safety

Why are system safety principles not used by all safety professionals? Suggest some ways to overcome the obstacles to wider adoption of system safety. Your response must be at least 75 words in length

Think about a time when you were required to accomplish a

Think about a time when you were required to accomplish a new or nonroutine task at work that had the potential to cause injury or illness. Discuss how a management of change process could be used to reduce the risks. Wh ...

A manchester signal has a data rate of 100 kbps using

A Manchester signal has a data rate of 100 Kbps. Using Figure 4.8, calculate the value of the normalized energy (P) for frequencies at 0 Hz, 50 KHz, 100 KHz.

Examproblem i-part a your systems analysis team is close to

Exam Problem I- Part A: Your systems analysis team is close to completing a system for Meecham Feeds. Roger is quite confident that the programs that he has written for Meecham's inventory system will perform as necessar ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

WalMart Identification of theory and critical discussion

Drawing on the prescribed text and/or relevant academic literature, produce a paper which discusses the nature of group

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro