1. Learning Objectives Structures Structure types
Pointers and structure types
Structures as function arguments

2. Structures Aggregate data type: struct Aggregate meaning "grouping"
Recall array: collection of values of same type
Structure: collection of values of different types
Treated as a single item, like arrays
Major difference: Must first "define" struct
Prior to declaring any variables

3. Structure Types Define struct globally (typically)
No memory is allocated
Just a "placeholder" for what our struct will "look like"
Definition: struct CDAccount Name of new struct "type" { double balance;  member names double interestRate; int term; };

4. Declare Structure Variable
With structure type defined, now declare variables of this new type: CDAccount account_1;
Just like declaring simple types
Variable account now of type CDAccount
It contains "member values"
Each of the struct "parts"

5. Accessing Structure Members
Dot Operator to access members
account_1.balance
account_1.interestRate
account_1.term
Called "member variables"
The "parts" of the structure variable
Different structs can have same name member variables
No conflicts

6. Structure Pitfall Semicolon after structure definition
; MUST exist: struct WeatherData { double temperature; double windVelocity; };  REQUIRED semicolon!

7. Structure Assignments
Simple assignments are legal between instances of same structure: apples = oranges;
Simply copies each member variable from apples into member variables from oranges
Sometime confusing, not recommend to use
Assign field by field, more accurate and clear
apple.price = oragnge.price;
apple.producer = orange.produce;

8. Initializing Structures
Can initialize at declaration
Example: struct Date { int month; int day; int year; }; Date dueDate = {12, 31, 2003};
Declaration provides initial data to all three member variables
Not commonly used

9. Initializing Structures (continued)
Initialize after declaration (more commenly used) struct Date { int month; int day; int year; }; Date dueDate;
dueDate.month =12;
dueDate.day = 31;
Duedate.year = 2003;

10. Using Pointers with Struct
The -> operator
Shorthand notation
Combines dereference operator, *, and dot operator
Specifies member of class "pointed to" by given pointer

11. Using Pointers with Struct (continued)
struct Date { int month; int day; int year; }; Date dueDate;
Date * P = &dueDate
P->month =12;
P->day = 31;
P->year = 2003;

12. Using Pointers with Struct (continued)
struct Date { int month; int day; int year; }; Date * P = new Date;
P->month =12;
P->day = 31;
P->year = 2003;

13. Structures as Function Arguments
Passed like any simple data type
Pass-by-value
Pass-by-reference
Pass-by-pointer
Can also be returned by function
Return-type is structure type
Return statement in function definition sends structure variable back to caller