Project #2 SOlution

The second project involves completing and extending the C++ program that evaluates statements of an expression language contained in the module 3 case study.




The statements of that expression language consist of an arithmetic expression followed by a list of assignments. Assignments are separated from the expression and each other by commas. A semicolon terminates the expression. The arithmetic expressions are fully parenthesized infix expressions containing integer literals and variables. The valid arithmetic operators are +, –, *, /. Tokens can be separated by any number of spaces. Variable names begin with an alphabetic character, followed by any number of alphanumeric characters. Variable names are case sensitive. This syntax is described by BNF and regular expressions in the case study.




The program reads in the arithmetic expression and encodes the expression as a binary tree. After the expression has been read in, the variable assignments are read in and the variables and their values of the variables are placed into the symbol table. Finally the expression is evaluated recursively.




Your first task is to complete the program provided by providing the three missing classes, Minus, Times and Divide.




Next, you should extend the program so that it supports relational, logical and conditional expression operators as defined by the following extension to the grammar:




<exp - '(' <operand <op <operand ')' |

'(' <operand ':' <operand '?' <operand ')' |

'(' <operand '!' ')'




<op - '+' | '-' | '*' | '/' | '' | '<' | '=' | '&' | '|'




Note that there are a few differences in the use of these operators compared to their customary use in the C family of languages. Their differences are:




In the conditional expression operator, the symbols are reversed and the third operand represents the condition. The first operand is the value when true and the second the value




when false




The logical operators use single symbols not double, for example the and operator is & not && The negation operator ! is a postfix operator, not a prefix one




There are only three relational operators not the usual six and the operator for equality is = not ==




Like C and C++, any arithmetic expression can be interpreted as a logical value, taking 0 as false and anything else as true




Your final task is to make the following two modifications to the program:




The program should accept input from a file, allowing for multiple expressions arranged one per line.







All results should be changed from double to int. In particular the evaluate function should return an int.




You may assume that all input to the program is syntactically correct.




Deliverables:




Deliverables for this project include the following:




Source code correctly implementing all required functionality. Your program must compile with Microsoft Visual C++ or any modern C/C++ compiler on your O/S.
Word or PDF file providing screen shots of successfully compiling and executing the program.



Description of the process and lesson learned while completing this project (to be included in the Word or PDF document).



A test plan that contains test cases that test all of the required operators. Each test case should include the expression and its expected value (to be included in the Word or PDF document).



Grading rubric:







Attribute
Meets
Does not meet
Functionality
40 points
0 points


Completes the program provided in
Does not complete the program


Module 3 by providing the three
provided in Module 3 by providing the


missing Classes:
three missing Classes:


Minus, Times and Divide.
Minus, Times and Divide.









Extends Functionality
20 points
0 points


Extends the program so that it
Does not extend the program so that


supports relational, logical and
it supports relational, logical and


conditional expression operators.
conditional expression operators.


All results should be changed
All results should be changed


from double to int. In particular
from double to int. In particular


the evaluate function should return
the evaluate function should return


an int.
an int.
Input
20 points
0 points


Accepts input from a file, allowing
Does not accept input from a file,


for multiple expressions arranged
allowing for multiple expressions


one per line.
arranged one per line.






Documentation and
20 points
0 points
submissions
Includes source code correctly
Does not Include source code


implementing all required
correctly implementing all required


functionality.
functionality.












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Program compiles with Microsoft
Program does not compile with


Visual C++ or any modern C/C++
Microsoft Visual C++ or any modern


compiler on your O/S.
C/C++ compiler on your O/S.


Includes Word or PDF file providing
Does not include Word or PDF file


screen shots of successfully
providing screen shots of successfully


compiling and executing the
compiling and executing the program.


program.






Does not include a description of the


Includes a description of the
process and lesson learned while


process and lesson learned while
completing this project (to be included


completing this project (to be
in the Word or PDF document).


included in the Word or PDF




document).
Does not include a test plan that




contains test cases that test all of the


Includes a test plan that contains
required operators. Each test case


test cases that test all of the
should include the expression and its


required operators. Each test case
expected value (to be included in the


should include the expression and
Word or PDF document)


its expected value (to be included




in the Word or PDF document).

















































































































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