When sam describes modeling the inputs and outputs of an is and understanding how they relate to other systems, she is describing

Ihave a music player on my phone. i can buy songs, add them to playlists and play them. obviously it would be redundant to store each song in each playlist; each playlist is just a list of pointers to the songs. for this lab you will simulate this behavior. your program will need to have options to: add songs to the system library (you will store the text of the first line of the song, rather than the audio) add playlists add songs to a playlist list playlists play a playlist list all of the songs in the library with a count of how many times each song has been played remove a song from a playlist remove a playlist remove a song from the library (and thus from all playlists that contain it) note that we will not be checking many error cases. in real programming this would be bad, you should usually try to recognize and respond to as many types of errors as you can. in the context of class we are trying to acquaint you with as many concepts as possible, so for the sake of educational efficiency we will not be checking most errors in this lab, you may assume that your user provides correct input. you may add all appropriate error testing if you wish, but we will not be testing for it.

Acase study allows a more detailed look at the life of a single subject than any other study.

Consider the following statements: struct nametype{string first; string last; }; struct coursetype{string name; int callnum; int credits; char grade; }; struct studenttype{nametype name; double gpa; coursetype course; }; studenttype student; studenttype classlist[100]; coursetype course; nametype name; mark the following statements as valid or invalid. if a statement is invalid, explain why. a.) student. course. callnum = "csc230"; b.) cin > > student. name; c.) classlist[0] = name; d.) classlist[1].gpa = 3.45; e.) name = classlist[15].name; f.) student. name = name; g.) cout < < classlist[10] < < endl; h.) for (int j = 0; j < 100; j++)classlist[j].name = name; i.) classlist. course. credits = 3; j.) course = studenttype. course;