Your backend for the the social network site, FriendWork, is not working very well. You need to improve it to help support it’s growing customer base. The updated backend will need to support the same functionality as the first, such as adding, removing, and printing friendships. However, this time the the updates such as add and remove will need to be done with more efficient functions/data structures. Remember that friendships go both ways, i. e. if A is friends with B, then B is also friends with A. Input Specification The input will begin with an integer q (q ≤ 500,000), number of queries to your webpage. The next q lines will each contain 1 server query. There are 3 query types. The first query type is the add query. The add query will begin with the word "ADD" followed by two names, a and b. The word "ADD" and the names will all be separated by a single space. This query implies the people named a and b have become friends. The second query is the remove query. The remove query will begin with the word "REMOVE" followed by two names, a and b. The word "REMOVE" and the two names will be separated by a single space. The remove query will denote that user a and b are no longer friends. The last query type is the list query. The list query will begin with the word "LIST" followed by one name, a, representing the user we wish to list the friends of. Each name will be at most 100 lower case characters and will contain no whitespace. No user will become a friend of themselves. No user will remove themselves as a friend. If a friendship is added, it will be between two users that are currently not friends. If a friendship is removed, it will be between two users that are currently friends. Output Specification For each list query print out on a line by itself the number of friends the user has. After which print out the names of each friend of the given user (in any order) each on their own line. Input Output Example Input Output 5 ADD alice bob ADD alice carol LIST alice LIST david REMOVE alice bob 2 bob carol 0 6 LIST alice ADD alice bob ADD alice david LIST alice ADD david bob LIST david 0 2 bob david 2 alice bob Explanation Please refer to the original document for assignment 1 Advice Two solutions to this problem both use BSTs. The first possibly easier to conceptualize solution uses 2 structs. A user_bst struct and a friend_bst struct. The BST is needed for both of them, because removing a user from someones friend list would be slow without a BST. Each node of the user BST would point to the root of a friend BST that stores all the friends the given user has. The other solution approach uses one BST node to store both the user and the friend BST. This makes it so there is less functions to create (and debug). However, there will be a slight memory overhead thanks to the extra pointers

program in C please

Which of the following kinds of programs displays an online advertisement in a banner or pop-up window on webpages, email, or other internet service? e

Calculating the "total price" of an item is tedious, so implement a get_item_cost method that just returns the quantity times the price for an item. by the way, the technical term for this kind of instance method is an accessor method, but you'll hear developers calling them getters because they always start with "get" and they get some value from instance attributes. in order to make the items sortable by their total total price, we need to customize our class. search the lectures slides for "magic" to see how to do this. see section 9.8 for an additional reference. the receipt class: this will be the class that defines our receipt type. obviously, a receipt will consist of the items on the receipt. this is called the composition design pattern. and it is very powerful. instance attributes: customer_name : it is very important to always know everything you can about your customers for "analytics", so you will keep track of a string customer name in objects of type receipt. date : the legal team has required that you keep track of the dates that purchases happen for "legal reasons", so you will also keep track of the string date in objects of type receipt. cart_items : this will be a list of the items in the cart and hence end up on the receipt. methods: 1. create a default constructor that can take a customer name as an argument, but if it gets no customer name, it will just put "real human" for the customer_name attribute. it should also accept a date argument, but will just use the value "today" for the date instance attribute if no date is given. the parameters should be named the same as the instance attributes to keep things simple. 2. add_item : self-descriptive. takes a parameter which we hope beyond hope is of type itemtopurchase and adds it to the cart_items. returns none. 3. print_receipt : takes a single parameter isevil, with default value true. returns a total cost of all the items on the receipt (remember to factor in the quantity). prints the receipt based on the following specification: for example, if isevil is true, and customer_name and date are the default values: welcome to evilmart, real human today have an evil day! otherwise, it should print: welcome to goodgo, real human today have an good day! then the receipt should be printed in sorted order like we discussed earlier, but whether or not it starts with the highest cost (think reverse), depends on the value of isevil. if it is evil, then the lowest cost items should print first, but if it is good, then it will print the highest cost items first. (cost meaning price*quantity). remember to return the total cost regardless! your main() function: the main flow of control of your program should go in a main() function or the program will fail all the unit tests. get the name of the customer with the prompt: enter customer name: get the date with the prompt: enter today's date then, ask the question: are you evil? your program should consider the following as true: yeah yup let's face it: yes hint: what do these strings all have in common? your program should consider all the following as false: no nah perhaps but i'm leaning no (just be glad you don't have to handle "yeah no.") okay enough horsing around. (get it? aggies? ! horsing! ) next, in the main() function, you will have to create a receipt object and start adding things into it using an input-while loop. the loop will prompt the user for the item name exactly as in the previous zylab (9.11). but unlike the previous zylab, the loop will terminate only if an empty string is entered for the item name. then, the price and the quantity will be prompted for exactly as in the previous zylab. create the itemtopurchase objects in the same manner as the previous zylab, but don't forget to add them to the receipt using your add_item instance method. then, the items on the receipt should be printed with the same formatting as in the previous zylab, of course with either "good" or "evil" ordering. however, on the last line, the total should be printed as follows: where 10 is replaced by the actual total. sample run here is what a sample run of the final program should look like: enter customer name: nate enter today's date: 12/20/2019 are you evil? bwahahahaha yes enter the item name: bottled student tears enter the item price: 2 enter the item quantity: 299 enter the item name: salt enter the item price: 2 enter the item quantity: 1 enter the item name: welcome to evilmart, nate 12/20/2019 have an evil day! salt 1 @ $2 = $2 bottled student tears 299 @ $2 = $598 total: $600

Alex’s family members live in different parts of the world. they would like to discuss the wedding plans of one of their distant relatives. however, alex wants all the family members to talk to each other simultaneously so that they can make decisions quickly. which mode of internet communication should they use? a. blog b. email c. wiki d. message board e. instant messaging