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Staircase is a Hackerrank problem from the Algorithms subdomain that requires an understanding of loops and string manipulation. In this post, you will learn how to solve Hackerrank’s Staircase problem and its solution in Python and C++.

Problem Statement and Explanation

Basically, we have to print a staircase of size n. The staircase should be right-aligned, composed of # symbols and spaces, and has a height and width of n.

Input Format

A single integer, n, denoting the size of the staircase.

Output Format

Print a staircase of size n using # symbols and spaces.

10 Days of JavaScript Day 3: Arrays, Try Catch and Finally & Throw

Day 3 of 10 Days of JavaScript challenge on Hackerrank is Arrays Try Catch and Finally amp Throw

In this series I will be sharing my solutions t

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Solve Me First - Problem Solving | HackerRank

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The Minion Game - HackerRank Solution Python

Two of the most popular options are HackerRank and LeetCode, both of which offer a large collection of coding challenges, contests, and learning resources. But which one is better for coding interviews?

In this blog post, we will compare HackerRank and LeetCode on several criteria, such as difficulty level, variety of questions and Interview preparation material. We will also give some tips on how to use both platforms effectively to ace your coding interviews.

Difficulty Level

One of the main factors to consider when choosing an online platform for coding practice is the difficulty level of the questions. You want to challenge yourself with problems that are similar to or slightly harder than the ones you will encounter in real interviews, but not so hard that you get frustrated and demotivated.

HackerRank and LeetCode both have a wide range of difficulty levels, from easy to hard, and they also label their questions according to the companies that have asked them in the past. However, there are some differences in how they categorize their questions and how they match the expectations of different companies.

HackerRank has four difficulty levels: easy, medium, hard, and expert. The easy and medium questions are usually suitable for beginners and intermediate programmers, while the hard and expert questions are more challenging and require more advanced skills and knowledge.

LeetCode has three difficulty levels: easy, medium, and hard. The easy questions are often basic and straightforward, while the medium and hard questions are more complex and require more logic and creativity.

Interview Preparation Material

HackerRank has a section called Interview Preparation Kit, which contains curated questions that cover the most common topics and skills tested in coding interviews. These questions are grouped by domains, such as arrays, strings, trees, graphs, dynamic programming, etc., and they have a difficulty rating from 1 to 5 stars. The Interview Preparation Kit is a good way to focus on the essential topics and practice the most frequently asked questions.

LeetCode also has a section called Explore, which contains curated collections of questions that cover various topics and skills, such as arrays, linked lists, binary search, backtracking, etc. These collections also include explanations, hints, solutions, and video tutorials for each question. The Explore section is a good way to learn new concepts and techniques and apply them to different problems.

In general, LeetCode tends to have harder questions than HackerRank, especially in the medium and hard categories. This is because LeetCode focuses more on algorithmic and data structure problems, which are often more abstract and require more optimization.

Variety of Questions

HackerRank has more diverse types of problems, such as database queries, regex expressions, shell commands, etc., which are more practical and relevant for certain roles and companies. Therefore, depending on your target role and company, you might want to choose the platform that matches their expectations better.

For example, if you are applying for a software engineering role at a big tech company like Google or Facebook, you might want to practice more on LeetCode, since they tend to ask more algorithmic and data structure problems. If you are applying for a data analyst or web developer role at a smaller company or startup, you might want to practice more on HackerRank, since they tend to ask more SQL or web-related problems.

Conclusion

In conclusion, both HackerRank and LeetCode are great platforms for coding interviews, and they both have their pros and cons. It really depends on your target role and company, as well as your personal preferences and learning style.

Problem Statement and Explanation

Add two numbers and return the sum. The numbers are provided as input to the function.

Input Format

int a - first number

int b - second number

Output Format

int - the sum of the two numbers

Solve Me First Solution in Python

Solve Me First Solution in C++

Explanation of Solution

The #include statements at the top of the code tell the compiler to include the necessary header files. These header files contain definitions for functions and variables that are used in the code.

The using namespace std statement tells the compiler to use the std namespace. This namespace contains many commonly used functions and variables, such as cin and cout.

The solveMeFirst function takes two integers as input and returns their sum. The function definition starts with the keyword int, which tells the compiler that the function returns an integer value. The function name is solveMeFirst, and it takes two arguments, a and b. The body of the function is enclosed in curly braces ({}). The first line of the function body returns the sum of a and b.

Disclaimer: We encourage you to solve this challenge yourself before reading our tutorial. We have provided a detailed explanation of the problem and our solutions to help you check your work.

Problem Statement

find the runner-up score in the given student score list or in simple words find the second maximum number in the array. There are n student score in the given list. we have to find the runner up score in the given list. The runner up score is the second maximum number in the list.

Suppose the given score for 5 student is 91, 92, 93, 94, 95. The runner up score should be 94. Because 94 is the second maximum number in the list. It's a useful problem to understand the list and sort concept in python.

Find the runner up score Solution in Python

Explanation

In the above code, we have created a function named find_runner_up_score() that takes a list of numbers as input and returns the second largest number in the list.

First, we used the set() function to remove duplicate elements from the list.

then we use the sorted() function to sort the list in ascending order.

then we use the [-2] index to access the second largest number in the list.

Time Complexity

We will solve linear equations using an inverse matrix in two steps. First, we will find the inverse of the matrix and then we will multiply the inverse matrix with the constant matrix.

For this, we will take an example of two linear equations with two variables. we will solve to find the value of x and y.

What is Linear Equation?

A linear equation is an equation of a straight line. It is a polynomial equation of degree 1. A linear equation can have more than one variable.

Standard Form of Linear Equation

The standard form of the linear equation is given below.

ax + by = c

Example of Linear Equation

3x + 8y = 5

4x + 11y = 7

How to Solve Linear Equations with Matrix Inversion? | Mathematics

A = [[3, 8], [4, 11]] B = [5, 7] X = ?

X = inverse(A) . B

How to Find Inverse of Matrix? | Python

Here is the Python code to find the value of x and y using an inverse matrix using Python and Numpy.

First, we will check if the matrix is invertible or not. If the matrix is invertible then we will find the inverse of the matrix and then we will multiply the inverse matrix with the constant matrix to find the value of x and y.

Driver Code

It's time to test our code. Here is the driver code to test our code.

def test_case(): A = np.array([[3, 8], [4, 11]]) B = np.array([5, 7]) solver = LinearEquationSolver(A, B) coff = solver.solve() print(coff) if __name__ == "__main__": test_case()

Output

[ -1. 1.]

Explanation

Here is the explanation of the output.

x = -1, y = 1

3x + 8y = 5

3(-1) + 8(1) = 5

-3 + 8 = 5

4x + 11y = 7

4(-1) + 11(1) = 7

-4 + 11 = 7

Conclusion

In this article, we learned how to solve linear equations using an inverse matrix. We learned how to find the inverse of the matrix and how to multiply the inverse matrix with the constant matrix to find the value of x and y.