CMPS 222 - Homework 3

Homework 3 - Operator Overloading

Due: Tuesday February 8, 2010 at 5:00pm

Coding Conventions

Use the same coding conventions as described in Homework 1. Additionally, make sure to indent each section of the class in the class definition.

Assignment

For this assignment, you will be modifying the Score class from Lab 3 to support a full range of operators. You are not required to use separate compilation (Lab 4) for this assignment.

Add the following constructors and operators to the Score class. Keep all the features that Lab 3 had in the class.

Conversion constructor for double. This constructor will take one double parameter. It will reject the double if it is negative (and set the millions and billions counters to 0). If the double is positive, it will do the following conversion: While the double is greater than THRESHOLD, it will increment the billions counter and subtract THRESHOLD from the double. Once it exits the loop, it will assign whatever remains in the double to the millions counter (be sure to typecase the assignment).
Copy constructor. This constructor will take a const reference to another Score object. It will copy the source's millions and billions counter to the current object.
Assignment operator, =. This function will take a const reference to another Score object. It will copy the source's millions and billions counter to the current object.
Update operator, +=. This function will take a const reference to another Score object. It will add the source's millions and billions counters to its own counters. It will then call normalizeScore().
Less-than operator, <. This function will compare two Score objects and return true if the left object has a lower score than the right object. Be sure with less-than (and all other relational operators) to compare both the billions and millions counters. For example, if left is 1 billion, 500 million and right is 2 billion, 300 million, then left is less than right even though left's millions are greater than right's millions.
Less-than-or-equal-to operator, <=. This function will compare two Score objects and return true if the left object has a score that is less than or equal to the right object.
Greater-than operator, >. This function will compare two Score objects and return true if the left object has a larger score than the right object.
Greater-than-or-equal-to operator, >=. This function will compare two Score objects and return true if the left object has a score that is greater than or equal to the right object.
Equality operator, ==. This function will compare two Score objects and return true if the left object has a score that is equal to the right object.
Inequality operator, !=. This function will compare two Score objects and return true if the left object has a score that is NOT equal to the right object.

Main Function

Your main() function is going to be a driver function that tests all of the operators and constructors you have added to the class. Note how the main() function for Lab 3 tests input, output, converting an integer, addition, the default constructor and so on. You will need to add additional testing for all of the above features.

In particular, your main function should test the following:

Test the doublt conversion operator by reading a double from the keyboard and creating a new Score variable from that double. You should then cout the new Score object to verify that it converted the double correctly. This is similar to the following lines from Lab 3 (but for doubles):
```
      int i;
      cout << "Enter a number for 'a': ";
      cin >> i;
      Score a(i);
      cout << "'a' is now " << a << endl;
```
Test the copy constructor by declaring a new Score variable and passing it an existing Score variable. Then cout both Score variables to confirm that they are identical.
Test the assignment operator by assigning one Score variable to another Score variable. Then cout both Score variables to confirm that they are identical.
Test the update operator by updating one Score variable with another Score variable. Then output the updated Score variable to confirm that its score has been increased appropriately.
Test all the relational operators with a series of if-else statements comparing two Score variables. For example, the following code tests the equality operator:
```
      if(a == b)
        cout << "'a' and 'b' are equal.\n";
      else
        cout << "'a' and 'b' are NOT equal.\n";
```

Email your complete Score class and main function to me.