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Dynamic programming problems are to be solved with tabular methods

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Memorize the value of pi You should always try to remember the value of pi as far as possible, 3.1415926535897932384626433832795, certainly the part in italics. The judges may not give the value in the question, and if you use values like 22/7 or 3.1416 or 3.142857, then it is very likely that some of the critical judge inputs will cause you to get the wrong answer. You can also get the value of pi as a compiler-defined constant or from the following code: Pi=2*acos(0)

3. JSON Class hinting ¶ There are only simple data types defined in JSON. To overcome this problem in a JSON compatible way a special property for objects is introduced. {"__jsonclass__":["constructor", [param1,...]], "prop1": ...} The object is then instantiated using the constructor, passing in the parameters. Once constructed the properties (prop1, ...) will be applied.

To give the serverside peer a chance to send messages to the client side peer, the client side peer may reopen communication by sending an empty HTTP POST.

--> {"method": "postMessage", "params": ["Hello all!"], "id": 99} <-- {"result": 1, "error": null, "id": 99} <-- {"method": "handleMessage", "params": ["user1", "we were just talking"], "id": null} <-- {"method": "handleMessage", "params": ["user3", "sorry, gotta go now, ttyl"], "id": null} --> {"method": "postMessage", "params": ["I have a question:"], "id": 101} <-- {"method": "userLeft", "params": ["user3"], "id": null} <-- {"result": 1, "error": null, "id": 101}

The Common Gateway Interface (CGI) is a standard protocol for interfacing external application software with an information server, commonly a web server. The task of such an information server is to respond to requests (in the case of web servers, requests from client web browsers) by returning output. Each time a request is received, the server analyzes what the request asks for, and returns the appropriate output. The two basic methods for the server to do this are the following: If the request identifies a file stored on disk, then return the contents of that file. If the request identifies an executable command and possibly arguments, then run the command and return its output. CGI defines a standard way of doing the second. It defines how information about the server and the request is passed to the command in the form of arguments and environment variables, and how the command can pass back extra information about the output (such as the type) in the form of headers.

In computing, a Uniform Resource Identifier (URI) consists of a string of characters used to identify or name a resource on the Internet. Such identification enables interaction with representations of the resource over a network (typically the World Wide Web) using specific protocols. Schemes specifying a specific syntax and associated protocols define each URI. Contents [hide]

A Uniform Resource Name (URN) functions like a person's name, while a Uniform Resource Locator (URL) resembles that person's street address. The URN defines an item's identity, while the URL provides a method for finding it. The ISBN system for uniquely identifying books provides a typical example of the use of typical URNs. ISBN 0486275574 (urn:isbn:0-486-27557-4) cites unambiguously a specific edition of Shakespeare's play Romeo and Juliet. In order to gain access to this object and read the book, one would need its location: a URL address. A typical URL for this book on a unix-like operating system might look like the file path file:///home/username/RomeoAndJuliet.pdf, identifying the electronic book saved in a local hard disk. So URNs and URLs have complementary purposes.

SOAP, originally defined as Simple Object Access Protocol, is a protocol specification for exchanging structured information in the implementation of Web Services in computer networks. It relies on Extensible Markup Language (XML) as its message format, and usually relies on other Application Layer protocols (most notably Remote Procedure Call (RPC) and HTTP) for message negotiation and transmission. SOAP can form the foundation layer of a web services protocol stack, providing a basic messaging framework upon which web services can be built.

A pattern must explain why a particular situation causes problems, and why the proposed solution is considered a good one. Christopher Alexander describes common design problems as arising from "conflicting forces" -- such as the conflict between wanting a room to be sunny and wanting it not to overheat on summer afternoons. A pattern would not tell the designer how many windows to put in the room; instead, it would propose a set of values to guide the designer toward a decision that is best for their particular application. Alexander, for example, suggests that enough windows should be included to direct light all around the room. He considers this a good solution because he believes it increases the enjoyment of the room by its occupants. Other authors might come to different conclusions, if they place higher value on heating costs, or material costs. These values, used by the pattern's author to determine which solution is "best", must also be documented within the pattern. A pattern must also explain when it is applicable. Since two houses may be very different from one another, a design pattern for houses must be broad enough to apply to both of them, but not so vague that it doesn't help the designer make decisions. The range of situations in which a pattern can be used is called its context. Some examples might be "all houses", "all two-story houses", or "all places where people spend time." The context must be documented within the pattern. For instance, in Christopher Alexander's work, bus stops and waiting rooms in a surgery are both part of the context for the pattern "A PLACE TO WAIT."

MathML is an XML standard by W3C and, embedded in XHTML,

A Voyage to Functional Programming in F#

Finally I settled on F#. Both LISP and F# are belong to functional programming (FP) paradigm.Functional programming is a complete different paradigm from imperative (and OO) programming.I found it terse as well yet I can understand it (though some of the concepts are new to me).The advantage is it can use .NET Framework. Thus it gives me a break from OOP and yet taps the power from the familiar .NET Framework.Therefore I decided to dive into it to seem whether functional programming can deliver its claims in terms of productivity and expression power.I would like to share my findings in this blog to those interested in learning functional programming.

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