Answer:
The power function can be written as a recursive function (using Java) as follows:
- static int power(int x, int n)
- {
- if(n == 0){
- return 1;
- }
- else {
- return power(x, n-1 ) * x;
- }
- }
Explanation:
A recursive function is a function that call itself during run time.
Based on the question, we know x to the 0th power is 1. Hence, we can just create a condition if n = 0, return 1 (Line 3 - 5).
Next, we implement the logic "x to the nth power can be obtained by multiplying x to the n-1'th power with x " from the question with the code: return power(x, n-1 ) * x in the else block. (Line 6 -8)
In Line 7, power() function will call itself recursively by passing x and n-1 as arguments. Please note the value of n will be reduced by one for every round of recursive call. This recursive call will stop when n = 0.
Just imagine if we call the function as follows:
int result = power(2, 3);
What happen will be as follows:
- run Line 7 -> return power(2, 2) * 2
- run Line 7 -> return power(2, 1) * 2
- run Line 7 -> return power(1, 0) * 2
- run Line 4 -> return 1 (Recursive call stop here)
Next, the return value from the inner most recursive call will be return to the previous call stack:
- power(1, 0) * 2 -> 1 * 2
- power(2, 1) * 2 -> 1 * 2 * 2
- power(2, 2) * 2 -> 1 * 2 * 2 * 2 - > 8 (final output)
Implementation hiding i<u>s the encapsulation of method details within a class</u>. Implementation can be interpreted as those specifications which can be altered without altering the correctness of an application. Wrapping data/methods within classes (descriptions of the way all objects of this type will look/act) in combination with implementation hiding is called encapsulation. Information users need to know about behaviors should be available without dependence on implementation specifications.
Here a 5 step recovery plan, I have been in IT for 8 years
1. Create a disaster recovery team.
The team will be responsible for developing, implementing, and maintaining the DRP. A DRP should identify the team members, define each member’s responsibilities, and provide their contact information. The DRP should also identify who should be contacted in the event of a disaster or emergency. All employees should be informed of and understand the DRP and their responsibility if a disaster occurs.
2. Identify and assess disaster risks.
Your disaster recovery team should identify and assess the risks to your organization. This step should include items related to natural disasters, man-made emergencies, and technology related incidents. This will assist the team in identifying the recovery strategies and resources required to recover from disasters within a predetermined and acceptable timeframe.
3. Determine critical applications, documents, and resources.
The organization must evaluate its business processes to determine which are critical to the operations of the organization. The plan should focus on short-term survivability, such as generating cash flows and revenues, rather than on a long term solution of restoring the organization’s full functioning capacity. However, the organization must recognize that there are some processes that should not be delayed if possible. One example of a critical process is the processing of payroll.
4. Specify backup and off-site storage procedures.
These procedures should identify what to back up, by whom, how to perform the backup, location of backup and how frequently backups should occur. All critical applications, equipment, and documents should be backed up. Documents that you should consider backing up are the latest financial statements, tax returns, a current list of employees and their contact information, inventory records, customer and vendor listings. Critical supplies required for daily operations, such as checks and purchase orders, as well as a copy of the DRP, should be stored at an off-site location.
5. Test and maintain the DRP.
Disaster recovery planning is a continual process as risks of disasters and emergencies are always changing. It is recommended that the organization routinely test the DRP to evaluate the procedures documented in the plan for effectiveness and appropriateness. The recovery team should regularly update the DRP to accommodate for changes in business processes, technology, and evolving disaster risks.
summary :an organization must develop a recovery team to create a disaster recovery plan that includes identifying and assessing disaster risks, determining critical applications, and specifying backup procedures. Other procedures may be included in the plan based on the organization. The recovery team and organization must then implement the DRP and follow through on the plan procedures. The DRP should be continually tested and maintained to consistently prepare the organization for evolving disasters and emergencies.
