# 辅导ICSI 404 Programming Assignment-

Computer Organization
University at Albany
Department of Computer Science
ICSI 404 – Spring 2022
Programming Assignment 2
Programming Assignment-2
Assigned: Tuesday, March 8
th, 2022.
Due: Tuesday, March 29th through your Blackboard account by 11:59 PM. Submissions with
20% penalty will be accepted by Thursday, March 31
st, by 11:59.
Objective
To acquire expertise in stack manipulation and management, subroutine linkage and return
conventions.
Description
You are to write a complete program in MIPS assembly language that evaluates arithmetic
expressions. The expressions must be fully parenthesized and include the following expressions
2. - (subtraction)
For simplicity all numbers in the expression will have only one base ten digit (0, 1, 2, 3, 4, 5, 6,
7, 8, 9) in them. Your program must be composed of four states: input, convert-to-postfix,
evaluate, and output states. At input data must be provided through the keyboard and stored as
an array of characters. After one expression is entered your program moves to the convert-topostfix
state. At this state your expression must be converted to the postfix notation using a
stack-based algorithm. Your program must then move to the evaluate state which evaluates the
postfix expression using a stack-based algorithm. At the output state your code must display the
complete expression in the postfix notation followed by the = symbol and the expression’s
numeric result.
Example
Some valid expressions and their corresponding postfix notations are:
a) ((1-3)+5) corresponds to 13-5+ in postfix notation.
b) (1-(3+5)) corresponds to 135+- in postfix notation.
Shown below is the Console display for expression a) above:
Console
Expression to be evaluated:
((1 - 3) + 5)
13-5+ = 3
Postfix Notation
2
Consider a set of all valid, completely parenthesized, infix arithmetic expressions consisting of
nonnegative integer digits, and the two operations +, -. The following definition gives all such
valid expressions:
1. Any nonnegative integer is a valid infix expression.
2. If a and b are valid infix expressions, then (a+b), and (a-b) are valid infix expressions.
3. The only valid infix expressions are those defined by steps 1 and 2.
The character string ((5-1) +3) is an example of a complete parenthesized expression. All valid
fully parenthesized infix expressions will have at least one operator.
Documentation
Your program must be developed using SPIM. It should be modularized and well commented. The
following is a tentative marking scheme and what is expected to be submitted.
1. External Documentation including as many pages as necessary to fulfill the requirements
listed below.
a. Title page.
b. [10%] Test documentation.
i. How you tested your program.
ii. Testing outputs.
c. [10%] User documentation.
i. How to run your program.
ii. Describe parameter (if any).
2. Source Code.
a. [75% total] Correctness.
The following expressions will be used for correctness verification.
i. [5%] (1+2)
ii. [5%] (1-(3+5))
iii. [10%] ((5-1) + 3)
iv. [10%] (4 – (1 – 2))
v. [10%] ((6-2) + (2-7))
vi. [15%] (((2+1) – 5) + (8 – 4))
vii. [20%] ((8+1) – (((3-1) +2) – 3))
b. [5%] Programming style
i. Layering.