CS255 - Computer Architecture and Assembler Programming                          
Homework Assignment 4
Due date: see Canvas

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1. Preparation

• To do this assignment, you must obtain a copy of the prepared files with the usual procedure.

  Use the assignment code hw4 to get the files for assignment 4.

• The files that you have copied into your ~/cs255/hw4 directory (in Emory's lab machines) should be these:

  test1.c: This program is used to test the isPerfect()( ) function Do NOT change this file test2.c: This program is used to test the isFib()( ) function Do NOT change this file hw4.c: The C program file contains the functions isPerfect() and isFib() You must edit and turn in this file for hw4

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• Assignment 4 is a C programming project.

  You must work on assignment 4 in the following way:

  Remote login to a lab machine then: cd to your cs255/hw4 folder Use nano to edit the hw4.c program file To compile a test program, use: For test1: gcc -o test1 test1.c hw4.c For test2: gcc -o test2 test2.c hw4.c To run a test program, use: For test1: test1 For test2: test2

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2. Assignment description

You must write 2 C functions in the hw4.c program file:

isPerfect(n): returns 1 if n is a perfect number, otherwise returns 0 isFib(n): returns 1 if n is a Fibonacci number, otherwise returns 0

The details of these 2 functons are given below (Section 3 and 4)

Use the provided prepared file hw4.c to write the functions:

/* ------------------------------------------------------------- isPerfect(n): returns 1 if n is a perfect number otherwise returns 0 Suppose f1, f2, ... fk are factors of n (Each: 1 <= f < n) n is a perfect number if f1 + f2 + ... + fk = n E.g.: 6 is perfect Factors of 6: 1, 2, 3 and 1 + 2 + 3 = 6 28 is perfect: 1 + 2 + 4 + 7 + 14 = 28 =============================================================== To compile test1, use this command: gcc -o test1 test1.c hw4.c To run test1, use this command: test1 ------------------------------------------------------------- */ int isPerfect(int n) { // Write this function for part 1 } /* ----------------------------------------------------- isFib(n): returns 1 if n is a Fibonannci number otherwise returns 0 The Fibonacci numbers defined found as follows: fib(0) = 1 fib(1) = 1 fib(n) = fib(n-1) + fib(n-2) =============================================================== To compile test2, use this command: gcc -o test2 test2.c hw4.c To run test2, use this command: test2 ----------------------------------------------------- */ int isFib(int n) { // Write this function for part 2 }

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3. Part 1 of homework 4

In part 1 of homework 4, write the isPerfect(n) function inside hw4.c:

isPerfect(n): returns 1 if n is a perfect number, otherwise returns 0 A number n is perfect, if the sum of its factors is equal to the the number itself. The number 1 is always a factor; but the number n is excluded. Example: 6 is a perfect number because the factors are: 1, 2 and 3 and their sum is equals to 6

Use the provided test1.c program to test your isPerfect(n) function.

When you finish writing the isPerfect() function, you can compile and test it with these commands:

Compile: gcc -g -o test1 test1.c hw4.c If no errors, run it with: test1 If your function passes all the tests, test1 will print out: Test 1 passed Otherwsie, it will print out which inputs failed the test

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4. Part 2 of homework 4

In part 2 of homework 4, write the isFib(n) function inside hw4.c:

isFib(n): returns 1 if n is a perfect number, otherwise returns 0 The Fibonacci numbers are defined by the relation: fib(0) = 1 fib(1) = 1 fib(n) = fib(n-1) + fib(n-2) The series of Fibonnaci numbers are: fib(0) = 1 fib(3) = 2 + 1 = 3 fib(6) = 8 + 5 = 13 fib(1) = 1 fib(4) = 3 + 2 = 5 fib(7) = 13 + 8 = 21 fib(2) = 1+1 = 2 fib(5) = 5 + 3 = 8 fib(8) = 21 + 13 = 34 and so on...

Use the provided test2.c program to test your isFib(n) function.

When you finish writing the isFib() function, you can compile and test it with these commands:

Compile: gcc -g -o test2 test2.c hw4.c If no errors, run it with: test2 If your function passes all the tests, test2 will print out: Test 2 passed Otherwsie, it will print out which inputs failed the test

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5. Extension request

• Use EGTAPI to make extension request as usual.

  If you need further instructions, read this write up: click here

• Use homework code hw4 to make extension request for homework 4

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6. Turn in instructions

• Use EGTAPI to turn in the program file hw4.c as usual.

  If you need further instructions, read this write up: click here

• Use homework code hw4 to turn in your program file hw4.c

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