Details of this Paper

dynamically allocated LINKED LIST,

Description

solution


Question

You will be modifying the program you wrote for programming assignment #4.;The program will store the realty listings data as a dynamically allocated LINKED LIST, instead of an array of;records.;The program will allow the realtors to both maintain and use the listings data.;1. Again, begin the program by asking whether to use existing information;If the user chooses to use existing data, ask the user for the filename of the data file.;Modify what happens when you verify that the given file exists. If the file does not exist;let the user choose whether to enter another filename or go to the action menu.;(NOTE: You will need to add the line;filestreamVar.clear();to clear the filestream error before trying another file);Continue to check each file entered by the user, until one exists, or the user chooses to go to;the action menu.;If the name of an existing file is entered, load the data from the file into a dynamically;allocated linked list.;The file data lines are still formatted as;111111 229700 0 80501-2345 Jones Realty;345678 176900 1 80513-2918 Metro Brokers;NOTE: There is no longer a specific size restriction on the number of listings that can be;entered, so the program will no longer keep track of the number of listings stored.;Instead when you try to allocate memory for each new node, you must validate that;memory was allocated, before using it.;2. After listing records have been read from a data file into the linked list (or the user chooses to proceed;to the action menu without reading records from an existing file), display an action menu of choices, as;follows;Display All listings to the screen (same as lab #4, but updated to use the linked list);If the list is empty, simply display a message stating there are no listings are stored.;Otherwise, display all listing data, one listing per line (with column headers).;Sample output lines;Asking Listing;MLS# Price Status Zip Code Realtor;------ ------- --------- ---------- ------------;111111 229700 Available 80501-2345 Jones Realty;345678 176900 Contract 80513-2918 Metro Brokers;Add listing(s) (same as lab #4, but updated to use the linked list);i. Create a new node to store the data for the new listing.;Validate that memory was allocated, before using it.;ii. Error check all data entered (use same specifications as lab #4) and store the data in the;new listing node.;iii. Insert the new listing node into the linked list (top or bottom ? your choice).;iv. Loop until the user chooses to exit, or memory can no longer be allocated.;Remove a listing (same as lab #4, but updated to use the linked list);If the list is empty, simply display a message stating there are no listings to delete.;Otherwise;i. Display MLS# of all listings, as choices for user;ii. Read the MLS# of the listing to delete.;iii. Verify the format of the entered MLS# is valid before using it to search (6-digits);? Loop until an MLS# with a valid format is entered.;iv. Search for the specified MLS#;? If the MLS# given is not found in the list, display an error message.;? If found, delete the node (and de-allocate the memory) and display a message;confirming that the listing has been deleted;Change asking prices (NEW function);Each line of a data file, CHANGES.TXT, contains an MLS number and a dollar amount.;Sample CHANGES.TXT data line;111111 25000;222222 10000;Match MLS numbers in the CHANGES.TXT file to the MLS numbers of listings in the;linked list, using the method described below;If the list is empty, simply display a message stating there are no listings to match;Otherwise;i. Verify that a CHANGES.TXT data file exists. If not, just issue an error message and;return to the menu.;ii. Read one line of data from the CHANGES.TXT file and attempt to match the MLS# in;to an MLS# in the listings linked list.;If a match is found;a) Reduce the asking price of the listing by the amount in the CHANGES.TXT file;b) Display the MLS# and the new asking price;iii. Loop, reading one line of data from CHANGES.TXT and trying to match the MLS#;until all lines have been read. Be sure to start over again at the top of the linked list each;time you loop.;NOTE: Some data lines may not match any listing MLS#, and some listings may have;multiple reductions in the CHANGES.TXT file.;Sample output lines;MLS number New Asking Price;---------- ----------------;111111 204700;333333 125900;111111 200700;iv. If there are NO matches to any items in the CHANGES.TXT file, issue a message saying;that no price reductions were made, before returning to the menu.;e. Exit the program (modified function)

 

Paper#68883 | Written in 18-Jul-2015

Price : $32
SiteLock