/// <summary>
/// Adds one dollar amound to another dollar amount
/// </summary>
/// <param name="amountToAdd"></param>
/// <returns>New Dollar Amount Value</returns>
public DollarAmount Plus(DollarAmount amountToAdd)
{
int newTotal = this.totalAmountInCents + amountToAdd.totalAmountInCents;
return(new DollarAmount(newTotal));
}
/// <summary>
/// Subtract one dollar amount from another dollar amount
/// </summary>
/// <param name="amountToSubtract"></param>
/// <returns>New Dollar Amount Value</returns>
public DollarAmount Minus(DollarAmount amountToSubtract)
{
int difference = this.totalAmountInCents - amountToSubtract.totalAmountInCents;
return(new DollarAmount(difference));
}