1. EECE.3220 Data Structures Instructor: Dr. Michael Geiger Spring 2019
Lecture 15:
Program 2 overview

2. Announcements/reminders
Program 2 due 3/21
Will implement dictionary
Each entry contains word, part of speech, definition
Load contents of dictionary from file or user input
Implement string-based commands to interact
Friday, 3/8: deadline for P1 resubmissions
Exams to be returned Friday
6/8/2019
Data Structures: Lecture 15

3. Data Structures: Lecture 15
Today’s lecture
Review
Constructors & initialization lists
Program 2 intro …
… and that’s it, since I have a Faculty Senate meeting on South Campus that starts at 3:30 …
6/8/2019
Data Structures: Lecture 15

4. Review: Initialization lists
How would we write Rectangle constructor(s)?
Could use Point set functions
Ideally, we’d like to call Point constructor as well
Create new Point every time we create Rectangle object
Use an initialization list
Explicitly calls constructors for member data
Requires parameterized constructor to be defined
Can be used for predefined types as well
Example:
Rectangle::Rectangle() : height(1), width(1), origin(0,0) {}
6/8/2019
Data Structures: Lecture 15

5. Data Structures: Lecture 15
Program 2
Model a dictionary using two classes
DEntry: single word, part of speech, definition
Dictionary: collection of DEntry objects
Gives practice with
Composition
String objects
6/8/2019
Data Structures: Lecture 15

6. Data Structures: Lecture 15
Program 2: main program
Main program handles commands
add word: Add 1 word to dictionary
add file: Add file contents to dictionary
print all: Print all entries in dictionary
print letter <L>: Print all entries containing words starting with letter <L>
find <word>: Search dictionary for <word>
exit: Exit the program
6/8/2019
Data Structures: Lecture 15

7. Data Structures: Lecture 15
Program 2: classes
Class definitions provided in spec, on site (shortly)
Spec also contains implementation notes
Feel free to use completely, modify, or simply write your own
As long as your program correctly implements commands, it’s a good solution!
6/8/2019
Data Structures: Lecture 15

8. Data Structures: Lecture 15
Program 2: DEntry class
class DEntry {
public:
void writeEntry(string w, string p,
string d);
void printEntry(ostream &out);
string getWord();
private:
string word; // Word
string part; // Part of speech
string defn; // Definition };
6/8/2019
Data Structures: Lecture 15

9. Program 2: Dictionary class
class Dictionary { public: Dictionary(); bool addWord(string w, string p, string d); bool addFile(string fname); bool find(DEntry &entry, string word); void printAll(ostream &out); void printLetter(ostream &out, char letter); private: DEntry entries[100]; // Array of dictionary entries unsigned size; // # entries actually in dictionary unsigned posn(string w); // Position in which word w // exists or should be placed };
6/8/2019
Data Structures: Lecture 15

10. Data Structures: Lecture 15
Final notes
Next time
Return exams
Reminders:
Program 2 due 3/21
Friday, 3/8: deadline for P1 resubmissions
6/8/2019
Data Structures: Lecture 15