OCH Chemicals & Systems Interview Questions and Answers

A linked list is a linear data structure where each element is a separate object with a pointer to the next element.

• Linkedlist allows for efficient insertion and deletion of elements

• It can be used to implement stacks, queues, and graphs

• Traversal is slower compared to arrays

• Examples include singly linked list, doubly linked list, and circular linked list

Hoisting is a JavaScript mechanism where variables and function declarations are moved to the top of their scope.

• Hoisting applies to variable declarations and function declarations

• Variables are initialized with undefined and functions are fully defined

• Hoisting only moves the declarations, not the assignments

• Example: console.log(x); var x = 5; // Output: undefined

• Closure is a function that has access to its outer function's variables, even after the outer function has returned...read more

This could refer to anything in javascript, please provide more context.

• Please provide more context for a specific answer.

• It could be a variable, function, object, or any other javascript construct.

• Without more information, it is impossible to provide a specific answer.

Box model is a way of representing HTML elements as rectangular boxes with content, padding, border, and margin.

• The box model consists of content, padding, border, and margin.

• Content is the actual content of the element.

• Padding is the space between the content and the border.

• Border is the line that surrounds the padding and content.

• Margin is the space between the border and other elements.

• To center an input tag, set margin-left and margin-right to auto and display to block.

useState is a hook in React that allows functional components to have state variables.

• useState is a built-in hook in React.

• It allows functional components to have state variables.

• It takes an initial state value and returns an array with the current state value and a function to update it.

• The state can be updated using the function returned by useState.

• Example: const [count, setCount] = useState(0);

Temporal dead zone is a behavior in JavaScript where a variable cannot be accessed before it is declared.

• Variables declared with let and const are hoisted but cannot be accessed before their declaration

• Trying to access a variable in its temporal dead zone results in a ReferenceError

• Temporal dead zone is a feature introduced in ES6 to improve JavaScript's scoping mechanism

Data types in JavaScript include primitive and object types.

• Primitive types include string, number, boolean, null, undefined, and symbol.

• Object types include arrays, functions, and objects.

• Typeof operator can be used to determine the type of a variable.

• Type coercion can occur when different types are used together.

Javascript is a scripting language used for web development, while Java is a general-purpose programming language.

• Javascript is interpreted, while Java is compiled

• Javascript is used for client-side scripting, while Java is used for server-side programming

• Javascript is loosely typed, while Java is strongly typed

• Javascript has a prototype-based object model, while Java has a class-based object model