Lab #12

This lab exercise contributes to your lab mark (3.67%).

1. We reserve the right to ask you to explain and demo your lab solutions.

2. You need to declare that you write the code all by yourself at the submission webpage.

3. We use the lab machines in CSC 159 for all marking purposes; make sure your C programs can be compiled (no warning messages, or any notes) and run on these machines.

4. Pack all your files ( ex12q1.c , ex12q2.c , lab12.h , makefile , spreadsheet.txt ,

s01a.txt , and other files if any) into by tar . You can execute the command

to validate that you can extract files successfully and that they work

well (all files in the same directory), where is a marking program we provided under

"Week 14" and you should download it in the same directory.

5. Submit your to the designated submission webpage as early as possible; no

late submission is accepted after the due date.

Objectives:

1. Practice on program design — free style programming, but your style is not marked

2. Practice on calling from stdlib.h ;

3. Practice on conditional compilation, Makefile, command-line arguments, FILE I/O, string I/O;

4. Old major items still to be practiced: arrays and pointers, function pass-by-value, recursion, struct

Descriptions:

Part 1: Sorting by calls

Download the file (http://webdocs.cs.ualberta.ca/~ghlin/CMPUT201/Lab12/spr

eadsheet.txt), which contains the term-work marks for the  students in the CMPUT 201 class. There are four components: Assignments, Quizzes, Labs and Exams, with their maximum marks and percentages (21, 8%), (14, 20%), (30, 33%) and (30, 39%), respectively. For every component, each student (their name in the format of "lastname firstname", in the spreadsheet) has a mark which is a floating-point number in the range , max_mark (the max_mark is the maximum mark

specified as in the above for the component). Design two C programs (i.e., executables called

and respectively) using conditional compilation to have the following

specified functionalities, and to determine the grade a student is to earn. Your programs must

use the following definition (which should be included in the required header file

For this part, the required source file is

and it contains the

function. You can

have other source files, and if any, name them as ex12q11.c , ex12q12.c , and so on. You are not recommended to have any other header file.

From (and other source files if any), compile a C program called sorting .

Run in the following way

the program reads in the data from the file (Note that we might use different

filenames and file contents, while keeping the number of students to be ; and so your program must accept command-line arguments and use FILE I/O.) and then display the following user interface:

The user enters XXX, which is one of {Name, Assignments, Quizzes, Labs, Exams, Total} (case sensitive), and your program sorts the students in ascending order of the values of XXX. Note that the student names are all distinct from each other (i.e., no ties), and sorting by  name follows the usual dictionary order using last name first and then first name; sorting by another struct member value might have ties, and in such a case breaks the ties using the student name.

Note that if XXX is not one of the defined strings, then your program terminates.

After the is read in, your program should calculate the total for each

student, but the grade is not assigned.

After the sorting, your program prints the sorted list of students, one line per student to

contain the values of all their members (use conversion specification point numbers), using the order specified in the above

that the first line of printing should be similar to the first line of

for all floating- definition. Note

to contain

the struct member names. In this way, if we save your program output (such as by redirection), then it will be very similar to spreadsheet.txt , except that it contains values for one or two more members .total (column "Total") and .grade (column "Grade") and the students are sorted in the ascending order of the given member value.

Note that if grades haven't been assigned yet, the column "Grade" should not be printed (since it is meaningless).

Your program terminates after the printing.

Sorting must be done by function calls to from stdlib.h . You do NOT implement

any sorting algorithm, but define the comparison functions to prepare the calls to qsort() .

Also from (and other source files if any), compile a C program called grading .

Run in the following way

./grading spreadsheet.txt

the program reads in the data from the file interface:

and then display the following user

Enter four cutoffs for grade assignment: DDD CCC BBB AAA

The user enters four floating-point numbers DDD, CCC, BBB, AAA, which are in the range and satisfy DDD  CCC  BBB  AAA, and your program assigns a student the

grade F if their .total < DDD, or the grade D if DDD  their .total < CCC, or the grade C if CCC   their .total < BBB, or the grade B if BBB  their .total < AAA, or the grade A if their .total  AAA.

Next, using the grade point values (F = 0, D = 1.0, C = 2.0, B = 3.0, A = 4.0), your program calculates the class average grade point, and prints the following (where f.ff is replaced by the actual value with 2 digits after the decimal point)

(For your self-checking, when the cutoffs are , the average grade point should be

.)

Afterwards, your program sorts the students in ascending order of their totals and prints the sorted list as described in Part 1 (i.e., using XXX = Total) into a text file named

(i.e., using FILE I/O, not through redirection). Note that now with grades being assigned, the column "Grade" should be printed out.

Your program terminates afterwards.

Both programs

contains the

and

are compiled out of the same set of files, among which function. Running these two programs should have the required

appearance as stated in the above. Particularly, does not ask for the cutoffs for grade

assignment, while does not provide options to sort.

You are responsible to compose a working (or makefile ), such that by executing the

command compiled.

both targets

and

(and the target

in Part 2) will be

Part 2: Finding all solutions to a Sudoku puzzle

We have introduced Sudoku puzzles when we talked about recursions. In general, a Sudoku puzzle has a unique solution, but in this exercise we generalize a puzzle to have any number of solutions (i.e., , , or more). According to Wikipedia, the number of Sudoku solution grids is approximately  .

In this exercise, we are given a puzzle to compute its number of solutions, and to print out some solutions.

The required source file

should contain the

function, in which we use an int -

type array game[9][9] to represent a puzzle where each element has a value from

(or otherwise the puzzle is invalid) and an element  represents an entry to be

filled. For example (which is saved as under Week 14),

You can have other source files, and if any, name them as ex12q21.c , ex12q22.c , and so on. You are not recommended to have any other header file.

Use the command

to compile your program called

(see

in Part 1). You

need to resolve any warning messages or notes during compilation. To run your program, use command

where

stores the puzzle and

is the number of solutions to be printed out. Note

that we will use different filenames and puzzles; and so your program must accept command-line

arguments and use FILE I/O. You can use to test your program, which has  solutions

(another puzzle the following:

under Week 14 should have  solutions). Your program prints out

The number of solutions to the puzzle is: n.

where is replaced by the actual number.

By the above command, your program prints out the smaller number, between  and , of solutions, each into a separate file. Assume  is a -digit  integer  (w/o  leading 's) below. The solution filename convention is  solXX...X.txt ; there are X 's in the index XX...X , which

ranges from to . For example, when        (then         ), then the solution filenames are  sol001.txt ,  sol002.txt , …, and so on; when         (then           ), then the solution filenames are sol1.txt , sol2.txt , …, and so on. If        , then the solution filename convention does not apply (i.e., no need to print out any solution).

Use to make sure each of your three programs runs correctly, without any

memory leak or error. At least mark deduction applies to leak or error.