NSArray

Please, find your tasks on NSArray and NSMutableArray bellow:

• Create NSArray, containing several strings, using literal declaration.
• Create mutable array from piviously created NSArray.
• Create an empty array and obtain its first and last element in a safe way.

Create NSArray, containing strings from 1 to 20:

• Get its shallow copy and real deep copy.
• Iterate over array and obtain item at index 13. Print an item.
• Make array mutable. Add two new entries to the end of the array, add an entry to the beginning of the array. Iterate over an array and remove item at index 5.
• Create new array of mixed numbers. Sort it in an ascending and descending order.