How to implement our own Vector Class in C++?
Given task is to implement a class in C++ which behaves just like the Vector class.
Vectors are same as dynamic arrays with the ability to resize itself automatically when an element is inserted or deleted, with their storage being handled automatically by the container. Vector elements are placed in contiguous storage so that they can be accessed and traversed using iterators. In vectors, data is inserted at the end. Inserting at the end takes differential time, as sometimes there may be a need of extending the array. Removing the last element takes only constant time because no resizing happens. Inserting and erasing at the beginning or in the middle is linear in time.
We can also make the vector class generic using templates.
Certain functions associated with the Vector that we will implement are:
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- void push(int data): This function takes one element and inserts it at the last. Amortized time complexity is O(1).
- void push(int data, int index): It inserts data at the specified index. Time complexity is O(1).
- int get(int index): It is used to get the element at the specified index. Time complexity is O(1).
- void pop(): It deletes the last element. Time complexity is O(1).
- int size(): It returns the size of the vector i.e, number of elements in the vector. Time complexity is O(1).
- int getcapacity(): It returns the capacity of the vector. Time complexity is O(1).
- void print(): It is used to print array elements. Time complexity is O(N), where N is the size of the vector.
Below is the implementation of our own Vector class.
Vector size : 5 Vector capacity : 8 Vector elements : 10 20 30 40 50 After updating 1st index Vector elements of type int : 10 100 30 40 50 Vector elements of type char : G H I J Element at 1st index of type int: 100 Element at 1st index of type char: H After deleting last element Vector size of type int: 4 Vector size of type char: 3 Vector capacity of type int : 8 Vector capacity of type char : 4 Vector elements of type int: 10 100 30 40 Vector elements of type char: G H I