These bit positions are represented by numerical values, as defined in list.h.

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1 CS305 Programming Assignment #3: Lovely Linked Lists with Starter Code Out: Feb 19, 015. Due: Mar 3, 015 by 11:00 pm on the CS305 Moodle site. Total points: 100. approximately 0% of the total homework grade. You must write a C program which has the following features (70 points): 1. It is invoked from the command line using exactly two parameters. Note that the name of the executable counts as the first parameter. The second parameter is a string to be used as input.. If an incorrect number of parameters is used, it should print an error message, the program s usage and return EXIT_FAILURE. 3. If the correct number of parameters is used, the program should: a. Treat the second parameter as a filename for a file in the current directory. The file must adhere to the following rules: i. Each line contains a pair of strings. ii. The first string is a US city name. iii.the second string is a 4-character string of 0 s and 1 s representing the city s points of interest. 1. The most significant bit, bit-3, is 1 if the city is a capital city.. Bit- is 1 if the city is in a coastline state. 3. Bit-1 is 1 if the city has a major league baseball team. 4. The least significant bit, bit-0, is 1 if Steve Vegdahl lives there. These bit positions are represented by numerical values, as defined in list.h. #define BIT_CAPITAL 8 // 0b1000 #define BIT_COAST 4 // 0b0100 #define BIT_BASEBALL // 0b0010 #define BIT_VEGDAHL 1 // 0b0001 b. Open and parse the file. If the file cannot be opened, the program must print a useful error message and return EXIT_FAILURE. Otherwise, insert each pair of values into a new node in a linked list, listnode, whose type is defined in list.h. i. The first string should be copied into the city field. ii. The second string should be converted into an int. The points-of-interest field should be initialized with the resulting int. c. Insert the new nodes into the list according to these ordering rules: i. Capital cities should be listed first, in lexicographical order. ii. Dr. Vegdahl s hometown should appear after capital cities. iii.all other cities should be listed in the subsequent nodes, in lexicographical order. d. Print each node of the linked list. Each node s contents should be listed as cityname (points of interest). If the node has a points-of-interest field of 0, the contents should be listed as cityname. See the example on page for guidance on formatting the points of interest. e. Free memory allocated to the linked list. You must extend an existing C program to fully implement a linked-list data structure to store an ordered linked-list. You are provided with an already-working C program: Download hw3.zip from the course website. The zipfile contains: list.c: A source file containing a partial implementation of a linked list data structure. list.h: A header file containing the function prototypes and constant declarations for list.c main.c: The main entry point of the program. makefile: A makefile to simplify compilation of hw3. 1

2 The working program has the following functionality: It is invoked using: $./hw3 inputfile. If the file inputfile does not exist, it prints an error message and exits gracefully. Otherwise, it opens inputfile and attempts to parse it in order to create a new linked list. It prints the linked list created. For example, 3.txt contains: Cheyenne 1000 Baltimore 0110 Milwaukie 0010 Portland 0101 The first line indicates that Cheyenne is a capital city since the most significant bit in the second string is 1. The second line indicates that Baltimore is in a coastline state and has a major league baseball team since bits and 1 are 1. The last line indicates that Portland is located in a coastline state and Steve Vegdahl lives there. Example compilation $ make gcc -c list.c gcc -o hw3 main.o list.o Example execution for starter program: $./hw3 3.txt Portland (poi) Milwaukie (poi) Baltimore (poi) Cheyenne (poi) You must write a C program which extends hw3 with the following features (70 points): 1. Extend parseinputfile() so that it appropriately converts the points-of-interest string read from the input file to an integer (main.c, near line 17). Then, extend printlist() so that it actually prints the points of interest for each city (list.c, near line 113)../hw3 3.txt Portland (Coast, Dr. Vegdahl s home) Milwaukie (MLB) Baltimore (Coast, MLB) Cheyenne (Capital). Extend insert() so that it inserts nodes into the list according to the ordering rules provided on page 1 (list.c, near line 70). For convenience, the ordering rules are repeated here: i. Capital cities should be listed first, in lexicographical order.

3 ii. Dr. Vegdahl s hometown should appear after capital cities. iii.all other cities should be listed in the subsequent nodes, in lexicographical order../hw3 3.txt Cheyenne (Capital) Portland (Coast, Dr. Vegdahl s home) Baltimore (Coast, MLB) Milwaukie (MLB) 3. Implement freelist() in list.c so that it frees all dynamically allocated nodes in the linked list (list.c, near line 135). These are the tests I will use to grade your submitted program: Test 1: Does the program handle one or > command-line parameter? (15 points) $./hw3 $./hw3 f f Incorrect number of parameters. usage:./hw3 <inputfile> Test : Does the program handle a one-line input file? (10 points) $./hw3.txt.txt was successfully opened. Cheyenne (Capital) Test 3: Does the program handle the example on page 3? (10 points) $./hw3 3.txt Cheyenne (Capital) Portland (Coast, Dr. Vegdahl s home) Baltimore (Coast, MLB) Milwaukie (MLB) 3

4 Test 4: Does the program handle inserting capital cities at the front of the linked list? (10 points) $./hw3 4.txt 4.txt was successfully opened. Bismark (Capital) Boston (Capital, Coast, MLB) Cheyenne (Capital) Test 5: Does the program handle a 17-line input file? (10 points) $./hw3 5.txt 5.txt was successfully opened. Bismark (Capital) Boston (Capital, Coast, MLB) Cheyenne (Capital) Eureka (Capital) Juneau (Capital, Coast) Montgomery (Capital, Coast) Salem (Capital, Coast) Topeka (Capital) WashingtonDC (Capital) Portland (Coast, Dr. Vegdahl s home) Arlington (Coast, MLB) Baltimore (Coast, MLB) Milwaukie (MLB) Nampa Provo Seattle (Capital, Coast) To receive full points, you must utilize good programming practice (30 points): Variables must have meaningful names and global variables must not be used. Preprocessor directives must be used for constant values. Code must be documented with useful comments and should use standard tabbing rules for good readability. 9 Code should not be redundant. If two snippets of code have similar functionality, make a function or write a loop. 6 A makefile must be used to compile the program and should be submitted with your homework submission. 4

5 All files opened by the program and all memory allocated to the program should be closed and freed before program exit. Only the main function and dedicated print functions should use printf(); other functions should not. Instead, the main() function should print a message depending on the return value of a function. Total 30 Students are given an opportunity for extra credit for hardening their programs against adversarial input. Feature 1: The program should make no assumptions about the length of the city names in the input file and should accept, store, print, and free arbitrarily long city names without error (10 points). Feature : The program should make no assumptions about the format of the file. If the file doesn t adhere to the rules of the input, the program should gracefully fail (15 points). No test cases are supplied for extra credit. Students must create their own test cases. If you completed any portion of the extra credit, please name your zip file <username>_ec.zip. To achieve maximum points on your submission, consider using this submission checklist before submitting your program to the Moodle course website: The name of my program files are main.c, aclist.c, aclist.h, and makefile. My program compiles successfully using a make command with my makefile. I ran all the tests (see above) to make sure my program executes correctly. I followed the five pieces of guidance on commenting programs. I compressed my files into a zipfile named with my username, e.g., crenshaw16.zip. I did not compress my files using.rar,.z7, or some other proprietary compression program. I did not compress a DIRECTORY of files. I uploaded my zipfile to Moodle. If you are missing any of the above checklist items, up to 0 points may be deducted from your score