, Read First Line
, Last Key
, Word Count
, Array Search
, Read Write Execute
, Numbers to Text
, Array Sum
, Category Tree
, Chain Link
, Crop Ratio
, Date Transform
, Log Parser
, View Count
, Language Teacher
, Unique Numbers
PHP is a widely used general-purpose scripting language that is especially well suited for web development.
A programmer should use a language as a tool, always taking advantage of language-specific data types and built-in functions.
Exceptions exist in most modern programming languages, making it important for a programmer to understand them and know how to handle them.
An array is a container of a fixed number of objects of a similar type. It is a fundamental component of most programming languages.
The string data structure is used to represent text. It is one of the most commonly used data structures. Therefore, every programmer should be skilled at string manipulation.
A stream is a sequence of data elements made available over time. It is particularly useful for tasks that may benefit from being asynchronous, including tasks such as I/O processing or reading from a file, and as such is important for developers to understand.
Arithmetic is a fundamental branch of mathematics. An understanding of arithmetic concepts, and their application, is important for every candidate.
Pass by reference
A good programmer should be familiar with when to use recursive functions, since they can provide elegant solutions for complex problems.
Pass by reference
The call by reference method of passing arguments to a function copies the reference of an argument into the formal parameter. Inside the function, the reference is used to access the actual argument used in the call. This means that changes made to the parameter affect the passed argument. This is one of two possible ways for passing an argument to a function so it should be known to any developer.
An associative array (or dictionary) is a data type composed of a collection of key-value pairs, where each possible key appears at most once in the collection. It is used when we need to access items by their keys.
A linked list is a linear collection of data elements where each element points to the next. It is a data structure consisting of a collection of nodes which together represent a sequence. It is usually used for advanced scenarios where we need fast access to the next element, or when we need to remove an element from anywhere in the collection.
An interface is used to define an abstract type that defines behaviors as method signatures. Instances of different types can implement the same interface and provide a way for a developer to reuse the code.
Object-oriented programming is a paradigm based on encapsulating logic and data into objects, which may then contain fields and procedures. Many of the most widely used programming languages are based on OOP, making it a very important concept in modern programming.
A session is a way to store information to be used across multiple pages. This is a technique that should be well known to any developer who works on web applications.
Everyone makes mistakes. A good programmer should be able to find and fix a bug in their or someone else's code.
Integer division is division in which the fractional part (remainder) is discarded. Knowing this is important for optimal implementation of some algorithms and for avoiding common bugs.
A regular expression (regex) is a special text string for describing a search pattern. It is a common way for extracting data from text.
Iteration is the act of repeating a process, or cycling through a collection. Iteration is one of the fundamental flow control tools available to developers.
Familiarity with data serialization to and from formats such as XML and JSON is important as it is commonly used for interprocess communication
Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. The design goals of XML emphasize simplicity, generality, and usability across the Internet. This is one of the most used formats for exchanging data over the web.
JSON is an open-standard format that uses human-readable text to transmit data objects consisting of attribute-value pairs. It's the most common data format used for asynchronous browser/server communication.
Every programmer should be familiar with data-sorting methods, as sorting is very common in data-analysis processes.
In object-oriented programming, inheritance is the mechanism of basing a class upon another class, retaining similar implementation. Inheritance allows programmers to reuse code and is a must know topic for every programmer who works with OOP languages.
When designing and/or analyzing an algorithm or data structure, it is important to consider the performance and structure of an implementation. Algorithmic thinking is one of the key traits of a good programmer, especially one working on complex or performance-critical code.