The container classes included in the C standard library serve as good illustrations of both the strengths and the weaknesses of the language. Gdels incompleteness theorems are two theorems of mathematical logic that demonstrate the inherent limitations of every formal axiomatic system containing basic. Waterfall BAwiki. This is admittedly my interpretation, but I have tried to provide links to all of the source material I have used so that you can do your own research if you dont agree with my conclusions. Also known as Phased Development, Plan Driven Development, Specification Driven Development, Cascade Model. Introduction. This is the 3rd major version of this wiki article and I thought it might be useful to provide a bit of introduction as to why I have written and continue to update such a long article about a discredited methodology like Waterfall. Several years ago my employer started making efforts to formally adopt some Agile processes Scrum specifically for some project types. Wanting to educate myself more I started doing Google searches and reading what material I could find. But my reading got hijacked as I came across descriptions of Waterfall over and over again that simply did not match the way we did it at my employer, or the way any other BA I had talked to had mentioned. So I got curious. Did my employer adopt some improved version of Waterfall that wasnt so rigid Were there actually people out there at some point advocating the highly rigid form of Waterfall I kept reading about on Agile oriented web sitesSo I started researching Waterfall. I found out where it supposedly originated from and dug up the original paper the Royce paper I discuss in depth below on the internet. And surprisingly, it had almost NOTHING in common with the rigid process I kept reading about on Agile sites. So I started researching more, and I was surprised to start coming across research papers that cited the Royce paper, but which completely mis characterized what it said. These were papers published in academic journals, not some random blog, so you would expect a higher level of quality. So I researched more and more and what fascinated me was the dichotomy of what people were consistently referring to as Waterfall, and what had actually been published in what were cited as the main sources of the Waterfall methodology. So thus was born this article on Waterfall. It is the result of my research, with all the sources I have used fully documented and for the majority of which I provide direct links where possible. LempelZivWelch LZW is a universal lossless data compression algorithm created by Abraham Lempel, Jacob Ziv, and Terry Welch. It was published by Welch in 1984. This article describes how LZW data compression works, gives a little bit of background on where it came from, and provides some working C code so you can experiment. Cryptology ePrint Archive Search Results 20171175 PDF Short Solutions to Nonlinear Systems of Equations Alan Szepieniec and Bart Preneel. It is not an apology for or a defense of Waterfall. Rachel Starr 2012. It is my best effort so far to show that there are at least two versions of the Waterfall model out there, and that the one that is most commonly known and referred to seems to have no basis in reality that I can find with the caveat that I may not have come across the right reference yet. You may not care about this. Or the history. Or what the sources actually said. You may find all the contextual information tedious and uninteresting. In that case, feel free to read the What is it section immediately below and then skip down past the Origins section and ignore everything in between. But if you do find it interesting, please read the whole article. If you know of references I havent touched on that are appropriate, please let me know. I am completely open to changing this article, but I want to make sure that most of the article is grounded in actual references. People can then form their own opinions based on the evidence. My conclusion after reading all that I have so far is the same as it was before I started doing all this research. There is no universally applicable development methodology. You need to tailor your development process to the situation at hand. Sometimes that will look very Agile, sometimes it will look very Waterfall, and sometimes have parts of both or neither. As has been repeatedly said, There is no silver bullet. What is it Strangely enough, this is probably the most controversial aspect of Waterfall. There seems to be a common understanding of what Waterfall is among a great many people in the technology world, but I would argue that that understanding is not supported by ANY of the references that are named as the source of Waterfall. The best initial description that I can come up with based on my reading is that the Waterfall model is a Systems or Software Development Life Cycle SDLC process model that is project management and solution design focused and which utilizes a highly planned, specification driven development process. It was probably the first formalized instance of a SDLC model, and nearly every software development model since has incorporated some of its features. What is now called Waterfall is frequently thought to have been first proposed by Winston W. Royce in a 1. 97. Herbert W. Bennington. However, the Waterfall model is also seen as highly controversial by some in the software development community. Indeed, some have gone so far as to call it a toxic concept,4 and the most costly mistake in the world. Partly, this is due to wide ranging differences in how people define the waterfall model. And I think it is partly due to a desire to have Waterfall as a straw man or boogie man specter to use for promoting personal agendas. These are due to both common misunderstandings of the history of Waterfall and because of the changing nature of what has been called Waterfall over time. In general, the way the Waterfall Model is described in current times seems to be highly dependent on the knowledge, agenda, and personal biases of the person describing it. Whats in a Name So why is it called the Waterfall model First, you need to know that Royce never used that term in describing his work and to understand that the Waterfall model name was assigned by others. Second, it helps to look at a common visual representation of the model such as the one below which is similar to the one used on Wikipedia Figure AIf you look at that diagram, the common description of Waterfall as each phase cascades down into the next, you know, like a waterfall begin to make sense. However, the oldest reference to Waterfall does not use the Waterfall name in that way, and allows for far more subtlety in interpretation. That earliest reference to Waterfall comes in a 1. Bell Thayer,1. Royce published his paper. The full quote is included below because I think it provides a good example of the way the Royce paper was perceived initially and that the Waterfall nomenclature was not initially meant the way it later came to be interpreted. Bell and Thayer say the following The evolution of approaches for the development of software systems has generally paralleled the evolution of ideas for the implementation of code. Over the last ten years more structure and discipline have been adopted, and practitioners have concluded that a top down approach is superior to the bottom up approach of the past. The Military Standard set MILSTD 4. Each of these is at a lower level of detail than the former, so the system developers are led through a top down process. The same top down approach to a series of requirements statements is explained, without the specialized military jargon, in an excellent paper by Royce 5 he introduced the concept of the waterfall of development activities. In this approach software is developed in the disciplined sequence of activities shown in Figure I. Figure 1 is a standard Waterfall diagram like the one immediately belowEach of the documents in the early phases of the waterfall can be considered as stating a set of requirements. Character and Boolean Data Types Java Questions Answers. This Section of our 1. Java MCQs focuses on Character and Boolean Datatypes of Java Programming Language. What is the numerical range of a char data type in Java View Answer Answer d. Explanation Char occupies 1. Advanced Launcher Kodi. Which of these coding types is used for data type characters in Java ASCIIb ISO LATIN 1c UNICODEd None of the mentioned. View Answer Answer c. Explanation Unicode defines fully international character set that can represent all the characters found in all human languages. Its range is from 0 to 6. Which of these values can a boolean variable contain True Falseb 0 1c Any integer valued true. View Answer Answer a. Explanation Boolean variable can contain only one of two possible values, true and false. Which of these occupy first 0 to 1. Unicode character set used for characters in Java ASCIIb ISO LATIN 1c None of the mentionedd ASCII and ISO LATIN1. View Answer Answer d. Explanation First 0 to 1. Unicode are same as those of ISO LAIN 1 and ASCII. Which one is a valid declaration of a boolean View Answer Answer c. Explanation Boolean can only be assigned true or false literals. What is the output of this programString argschar arrayvariable newchar1. System. out. printarrayvariablei i a i i i i ib 0 1 2 3 4c i j k l md None of the mentioned. View Answer Answer a. Explanation None. What is the output of this program String argschar a A a System. View Answer Answer a. Explanation ASCII value of A is 6. What is the output of this program String argsboolean var. System. out. printlnvar. System. out. printlnvar. View Answer Answer c. Explanation None. What is the output of this program String argsboolean var. System. out. printlnvar. View Answer Answer d. Explanation boolean operator always returns true or false. What is the output of this program String argschar var. A char var. 2 a System. View Answer Answer b. Explanation ASCII code for A is 6. Sanfoundry Global Education Learning Series Java Programming Language.