Midterms

Written by Josh Beto

Problem 1:

Define a class called Parser that represents a parsed sentence. Each word in the sentence is whitespace character separated like '\n' and ' '

• You should store a vector<string> words that represents each parsed word in a given sentence

• You need to implement functions that do the following:
  • Constructor that parses a given string

    Parser p("This is a sentence");
    // p should store a vector<string> words as follows:
    // ["This", "is", "a", "sentence"]
    

  • Prints out each word in the sentence on each line

    Parser p("This is a sentence");
    p.print();
    /*
    This
    is
    a
    sentence
    */
    

  • Returns a word at a given index. Does not change any private variables.

    Parser p("This is a sentence");
    string s = p.getWord(1);
    cout << s << endl; // prints out 'is'
    

  • Changes a word at a given index. Does not return anything.

    Parser p("This is a sentence");
    p.changeWord(3, "string"); // Changes the `vector<string>` words to ["This", "is", "a", "string"]
    

  • Filters out parsed words based on a given word

    Parser p("This is not a sentence"); // Changes the `vector<string>` words to ["This", "is", "a", "sentence"]
    p.filter("not");
    p.print();
    

• Note: Don’t worry about any out of bounds error checking

Problem 2:

Define a class called Wallet that stores money

• You should store money as unsigned dollars and unsigned cents

• You need to implement the following functions:

  • Constructor that uses an initialization list to take in unsigned dollars and unsigned cents. If the cents >= 100, convert the extra cents to dollar amounts

    Wallet w(5, 70); // 5 dollars and 70 cents
    Wallet w2(10, 230) // 12 dollars and 30 cents
    

  • Constructor that takes in no arguments and initializes dollars and cents to 0

    Wallet w(); // 0 dollars and 0 cents
    

  • Overload operator+ to take in another Wallet object and return the sum Wallet object

    Wallet w1(5, 70);
    Wallet w2(30, 80);
    w3 = w1 + w2; // w3, dollars = 36, cents = 50
    

  • Setter and getter for unsigned dollars
  • Setter and getter for unsigned cents
  • Print function that prints out the dollars & cents as follows:

    Wallet w(5, 70);
    w.print(); // prints out $5.70
    

Problem 3:

Create a class called AttendanceSheet.

• Define any neccessary structs or classes
• Specifications:
  • Constructor that takes in an integer, which is the number of students enrolled in the class, and a string date, the current date of attendance
  • Stores a list of students that have signed in to class today
    • Students have an integer ID and a name
  • Has a function that adds students to the attendance sheet. Each student enrolled must be unique, no duplicate sign-ins!
  • Has a function that evaluates if the class is cancelled. A class is cancelled when the number of signed in is less than 20% of the total number of students enrolled.
  • Has a function that clears the attendance sheet for the next session
  • Has a function that outputs the list of students to a file called 'attendance-<date>.txt' i.e. attendance-October-1st-2018
    • The students will be printed out each on a new line, with their <name> followed by <SID>
    • i.e.

      Alice 1203
      Bob 7820
      ...
      

Problem 4:

Come up with a definition for a University class

• You do not need to implement any of the functions, just declare them

• Specifications:

  • A list of enrolled students. Students have an SID, major, name, and year. In this university, a student immediately graduates after completing their 4th year.
  • A list of professors. Professors have a name and research specialty
  • The ability to sort the students in alphabetical order based on their name
  • Get a list of students that are graduating at the end of the year
  • The ability to add students by passing in the name of a file. Assume all new students are freshman. The file is ordered as follows:
    • Each line of the file denotes a different student.
    • Lines are ordered as follows:
      • <SID> <major> <name>
  • The ability to remove students that are graduating at the end of the year.
  • The ability to add a professor by passing in a name and research specialty.

Conceptual Questions

• Why are you allowed to chain together the << and >> operator? i.e. cout << "1" << "2" << "3" << endl;
• const int add(const string &s) const - What does each of the 3 const mean?
• Pass by reference vs. pass by value
• What happens to the left hand side of the + operator when you overload it in a class?
  • i.e. ```cpp class IntExample { private: int i; public: IntExample(int); IntExample operator+(IntExample); };

  /* … */

  int main() { IntExample i(6); IntExample j(9); i = i + j; // What happens to the left side, ‘i’, when you call the + operator. } ```