Fundamental Concepts of Arrays

An array is a collection of elements of the same data type stored in contiguous memory cells. It has a fixed size and is by default passed by reference to a function.

Eg. int arr[6] = {4, -3, 8, 5, -1, 6};

It initializes an integer array 'arr' storing 6 elements.

Assuming the size of an integer to be 4 bytes and base cell address to be 2000. It can be represented as -

Arrays are stored in contiguous memory cells

A dynamic array is similar to a static array but it has the ability to automatically resize itself when an element is inserted or deleted.

They are available as vectors in C++ and likewise lists in Java.

Eg. list<int> l; vector<int> v;

Vectors are slightly less efficient than static arrays due to the occasional resizing and copying of elements.

The amortized time complexity of insertion in a dynamic array is O(1).

[Amortized Time complexity = No. of operations / No. of pushbacks]

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