CS 2213 Advanced Programming, Spring 2001 Programming Assignment 2

Due In Class, March 27, 2001

Part 0: Fixed size arrays

Create a directory called assign2 for this assignment. Make a subdirectory of this called part0.

Copy all of the files from /usr/local/courses/cs2213/spring2001/assign2 into this directory. You should have 4 files: a makefile, a header file (.h) and two test files (.in).

Your program will read in a two dimensional array of characters having ROWS rows and COLUMNS columns. ROWS and COLUMNS are constants defined in the header file. It will then read in a number of words and attempt to find them in the array moving horizontally (left or right), vertically (up or down) or diagonally (4 directions). For each word it will print the word and where it found it in the array with a description of its direction.

You will write the following functions and put them in wordsearch.c. These have prototypes in wordsearch.h

int fillArrayFixed(char a[ROWS][COLUMNS]);

This will read characters from standard input to fill the array. Each line of input will contain COLUMNS characters. The number of lines read will be ROWS. Return 0 on failure and 1 on success. Convert all lower case letters to upper case. If you find anything other than a letter, this is an error. Stop reading and return 0. Make sure you read and test for the newline at the end of each line.

This prints the array to standard output, one row per line with no spaces between the characters.

This reads one line from standard input into the buffer w having size size. It converts lower case letters to upper case. Any input other than letters (upper or lower case) is considered an error. Return 0 if an error occurs (the line was too long to fit, an invalid character was entered, or the line ended without any characters) and 1 on success. Read until a newline is found but discard the newline. If this returns success, w should contain a string of upper case letters which does not include a newline.

This searches the array for the word s. If not found it returns the value FOUND_NOT defined in the wordsearch.h. If found, it returns one of the FOUND_ constants defined in wordsearch.h indicating its direction and sets *xp and *yp the the coordinates of the start of the word.

Write a main program in driver.c that starts by printing a line in the form:
This program was written by ...
It then reads two integers from standard input using:
scanf("%d%d\n",&rows,&columns);
It checks that rows is the same as ROWS and columns is the same as COLUMNS. If not, this is an error that should be reported. If these are OK, the program uses fillArrayFixed to read in the array and then uses getWord in a loop to read words until an error occurs. The size parameter for getWord should be at least as big as the larger of ROWS and COLUMNS. For each word read in, searchFixed is called and the results are printed using one line for each word.

The output produced for each input word should contain the word, and whether or not the word was found. If the word was found, the row and columns numbers should be given along with a description of the direction. For this output only, report the row and column numbers starting at 1 rather than 0. One way to easily get a description of the direction is to use the following array:

   char *directions[] = {"not found","across","down","backwards","up",
                        "diagonal down", "diagonal down and back",
                        "diagonal up", "diagonal up and back"};

Try to format your output so that it looks something like:

                word    row column direction
             POINTER      1      1 down
           KERNIGHAN      3      2 across
             RITCHIE      6      7 backwards
            OPERATOR      7      9 backwards
            ...

Part 1
Make a directory called part1 for this. Copy everything from your part0 directory into the part1 directory. Replace fillArrayFixed, printArrayFixed, and searchFixed with the following:

int fillArray(char *a, int rows, int columns);
void printArray(char *a, int rows, int columns);
int search(char *a, int rows, int columns,char *s, int *xp, int *yp);

Read in the rows and columns as before and use these to create your array (using malloc). Your functions will have to do the array subscripting with a calculation. Test your program with the files test1.in and test2.in. The first one should give the same results as for Part 0.

Part 2
This part is optional and is for extra credit (not much).
Create a part2 directory for this one. Copy all of your Part 1 files into this directory and modify the programs so that they will find all occurrences of the words, not just one.

Handing in your assignment
Use the cover sheet as your first page. Fill in the table of contents with the appropriate page numbers. Make sure there are no lint warnings that should not be there.