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How to write Java Program

In order to write Java code, use any of the IDE’s available. Create a project say “sample” and then create a class say “DemoPrint” in IDE. By convention the class names should be nouns with each internal word capitalized. In java, code is written inside a class. Let’s say we want to print a statement… read more »

What is Java and How It Works

Java is one of the very important and commonly used programming languages in the industry. It’s a free, secure and reliable and fast platform. Most of the applications and websites work only if java is installed in the computer. For example : It is used in websites like Google Drive, bank websites, Android apps, trading… read more »

Installation of Java on MAC OS

In order to install Java on MAC OS we need to follow some steps. Here are the things required : Install JRE Install JDK Install IDE Install JRE Download JRE. Go to Google search engine and search for jre 8. See Fig 1.   Click on Java SE Runtime Environment 8 – Downloads – Oracle… read more »

Categories of software testing

Categories of Testing Functional Non Functional Maintenance Functional Testing : It is a type of black box testing where internal structure is rarely considered and functions are tested by giving inputs and the outputs are examined by comparing it with the expected results.It describes the purpose of the system. This type of testing makes sure that… read more »

Different types of Software Testing

Software testing is a procedure to check whether the expected results match to the actual results of the code.In testing.It is made sure that code doesn’t have any semantic or syntax errors. Any gaps , missing code or requirements are identified. For example : Consider a source code to add two numbers.If I give input of… read more »

Methods of Software Testing

Methods of testing Manual Automated Manual testing : It is done by testers and developers.Refer to Fig 1 for the steps followed in manual testing. Automation testing : It is done by software systems.Refer to Fig 2 for the steps followed in Automation testing. Differences between Manual and Automation testing : Refer to Fig 3

Big Omega(Ω) Notation

Ω Notation provides the asymptotic lower bound on the function. A function needs to satisfy some conditions in order to be in Ω notation.Ω(g(n)) is the best case running time  of function g(n) within a constant factor. Ω(g(n)) = {f(n): there exist positive constants c and n0 such that 0 ≤ cg(n) ≤ f(n) for all n… read more »

Dijkstra’s algorithm

Dijkstra’s algorithm is way of finding shortest path from a source vertex to sink in a given connected and weighted graph. It is somewhat similar to Prim’s algorithm and it works for directed as well as undirected graphs. The step by step process is specified below : Source vertex is chosen and marked. Mark distances at all… read more »

Big O Notation

  It gives rate of growth of step count function(f(n)) in terms of simple function(g(n)) and defines the asymptotic upper bound on function(Fig 1). To simplify the estimation for running time,constants and lower order terms are ignored. The function needs to satisfy following conditions in order to be in Big-O class.Given functions f(n) and g(n),we… read more »

Time and Space Complexity

Before defining the actual term complexity, let us discuss about few real life scenarios. Take an example of railway reservation counter, people go there to book their tickets. The time to book tickets will depend on  how many service windows are available, queue size and time taken by each representative. A person will either go… read more »