Propbuynsell Interview Questions and Answers

Memoization is a technique used in programming to optimize performance by storing the results of expensive function calls and returning the cached result when the same inputs occur again.

• Memoization helps reduce redundant calculations by storing the results of function calls in a cache

• It is commonly used in dynamic programming and recursive algorithms to improve performance

• Example: Fibonacci sequence calculation can be optimized using memoization to store previously calculate...read more

Lazy loading is a technique used in web development to defer loading of non-essential resources until they are needed.

• Lazy loading helps improve page load times by only loading resources when they are required.

• It is commonly used for images, videos, and other media files on websites.

• Lazy loading can be implemented using JavaScript libraries like Intersection Observer or by using native browser features like loading='lazy' attribute for images.

Callback hell is a situation where multiple nested callbacks make the code difficult to read and maintain.

• Occurs when multiple asynchronous operations are nested within each other

• Can lead to unreadable and unmaintainable code

• Can be avoided by using promises or async/await

Prop drilling is the process of passing down props through multiple levels of components in React.

• Prop drilling can lead to complex and hard-to-maintain code.

• It can be avoided by using Context API or Redux for state management.

• Example: Passing props from a parent component to a deeply nested child component through intermediate components.

Dependency injection is a design pattern in which components are given their dependencies rather than creating them internally.

• Dependency injection helps in making components more modular and easier to test.

• It promotes loose coupling between components.

• There are three types of dependency injection - constructor injection, setter injection, and interface injection.

Quick sort is a popular sorting algorithm that uses a divide-and-conquer approach to sort elements in an array.

• Quick sort picks a 'pivot' element from the array and partitions the other elements into two sub-arrays according to whether they are less than or greater than the pivot.

• It then recursively sorts the sub-arrays.

• The pivot selection can greatly affect the efficiency of the algorithm. Commonly used methods include selecting the first element as the pivot, the last eleme...read more