The concept of Data Structures and Algorithms in programming are used for tackling real time problems. The general idea behind using the programming concepts is to make everything time efficient and solve every possible problem in as less of a time as possible.
In this regard, the concept of array is certainly one of the major programming concepts in DSA that is extremely essential from the perspective of technical interviews. You will find the Array interview questions in the online test and the Technical/HR round.
In this blog, we are going to be unfolding all the different methods and algorithms that are commonly used for solving the array based problems.
But before we start, let’s discuss what sort of questions are faced in the array interviews!
What are Array Interview Questions?
For the experts at the field of programming, Array remains an important part of their journey right from the beginning till their placement.
By understanding the types of array interview questions commonly asked in tech interviews, you can pursue technical positions such as-Software Developer. It saves you a lot of time as an SDE developer.
During a technical interview, the interviewer might ask a bunch of Array based questions in order to test your coding skills and problem solving ability.
That is why it is important to understand that the array concept has more real-time applications than you might imagine.
From arranging phone books to arranging data in a sequential order, the use of arrays has never gone away.
Some of the popular coding languages such as Python, Java and C++ provide an easy interface for solving the array based problems via a series of pre-set algorithms.
Now since you are here to learn more about solving array problems, we have selected some of the most commonly used algorithms that you can implement to easily solve the array interview questions.
What methods to use for solving Array based questions?
The concept of Data Structures and Algorithms is extremely vast. This is because there are more than at least two methods for solving any coding problem that one can think of.
This certainly raises the bar with increasing levels of difficulty in the programming question. Luckily, we have some of the best approaches and strategies that are not only easier to learn but are also time efficient.
let’s have a look.
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Using Nested Loops
The simple or nested loops are one of the most common approaches that provide an easier solution to any programming problem by solving it step by step.
There are several variations to this approach. Check them out as follows:
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Input-based strategy
The input based strategy processes a single input at each level of iteration thus deriving a partial solution to the problem.
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Output-based strategy
Much like the input-based approach, the output based strategy focuses on adding an output at each level of iteration thus building a partial solution to the problem.
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Iterative improvement method
In this approach, we presume a few solutions to the problem statement and continuously improve on them in order to attain the desired solution.
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Using Divide and Conquer Method
The divide and conquer approach is one of the highly used algorithms for solving programming problems. This method has been repeatedly asked in several technical interviews such as the Microsoft, Amazon, Google and Goldman Sachs interview questions.
So, what is the divide and conquer approach?
Theoretically, the divide and conquer approach is exactly what the name suggests. We start with dividing a given problem statement into subproblems and try to analyse the results in order to form the output.
Because of its nature, the divide and conquer approach naturally demands the use of the recursive algorithm.
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Using Binary Search Algorithm
This approach can be effectively used for solving the array interview questions where we are provided a sorted array.
The idea is to form a Binary Search Tree and start solving several subproblems at the same time using the O(logN) time complexity.
In order to achieve this you would have to change a few standards of the existing Binary Search algorithm depending on the conditions raised in the problem statement.
The main idea is to initiate the mid index of the BST and iterate the left or the right halves for the arrays.
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Using Sliding Windows Approach
This approach is more commonly used for solving programming problems based on strings and arrays.
We refer to the Windows as the continuous sequence of elements that contain a start and an end index.
Start by selecting an element from the array and after performing a few operations we eventually slide it in the forward direction after incrementing the right or the left ends.
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Using DFS and BFS
Otherwise known as the Breadth First and the Depth First Search algorithms, this problem essentially uses the Binary Search Tree for finding the results.
The main idea is to find something that resembles the closest to the root. For this we usually prefer the BFS otherwise in order to perform an in-depth search, we use the DFS approach.
Here are a few applications of both the approaches:
- The pre-order traversal method in a Binary Tree is used for situations where we are required to search all the nodes of a Binary Tree
- We also use a post-order traversal for exploring the leaf nodes of the Binary Tree before we inspect the internal nodes
Final Thoughts
Did you know?
As per some real life job experiences, the concepts of DSA only take up 5% of your entire job role!
This data might seem smaller than expected but it is also important to note that Arrays take up a huge portion of interview questions than any other programming concept.
That is why some of the most popular coding tests such as Infosys, Microsoft, HashedIn and Goldman Sachs interview questions, have higher chances of including the array questions majorly.
If you are interested in checking out array interview questions for your next interview then do check out our website.
