Paytm Insider Software Development Engineer 1 Interview Questions and Answers

The function checks if a string is a substring of another string.

• Use the built-in string methods like 'indexOf' or 'includes' to check for substring.

• If the language supports regular expressions, you can also use them to find substrings.

• Consider the case sensitivity of the strings when comparing.

Code to multiply two matrices of dimension M*N and N*K.

• Create a result matrix of dimension M*K.

• Iterate through each row of the first matrix.

• For each row, iterate through each column of the second matrix.

• For each element in the row of the first matrix, multiply it with the corresponding element in the column of the second matrix.

• Sum up the products and store the result in the corresponding position of the result matrix.

• ...read more

SQL query to perform matrix multiplication using two tables with row, col, and value columns.

• Use JOIN operation to combine the two tables based on matching row and col values.

• Use GROUP BY clause to group the result by row and col values.

• Use SUM function to calculate the dot product of corresponding row and col values.

• Use INSERT INTO statement to insert the result into a new table.

Prototype in JavaScript is an object that is associated with every function and object by default.

• Prototype is used to add properties and methods to an object.

• It allows objects to inherit properties and methods from other objects.

• Modifying the prototype of a function affects all instances of that function.

• Prototypes can be used to create new objects based on existing objects.

• The prototype chain allows for property and

Classes in JavaScript are written using the class keyword.

• Use the class keyword followed by the class name to define a class.

• Use the constructor method to initialize class properties.

• Add methods to the class using the class prototype.

• Use the new keyword to create an instance of the class.

The number of different ways to climb a ladder of N steps by taking 1 or 2 steps at a time.

• This is a classic problem that can be solved using dynamic programming.

• The number of ways to climb N steps is equal to the sum of the number of ways to climb N-1 steps and N-2 steps.

• The base cases are when N is 0 or 1, where there is only 1 way to climb the ladder.

• For example, for N=4, there are 5 different ways: [1, 1, 1, 1], [1

Print a square matrix in spiral order

• Start by defining the boundaries of the matrix

• Iterate through the matrix in a spiral pattern, printing each element

• Adjust the boundaries after each iteration to move inward

• Repeat until all elements are printed

Retrieve the second highest marks obtained by each student from a table with student name, subject, and marks.

• Use the RANK() function to assign a rank to each row based on the marks in descending order.

• Filter the result to only include rows with rank 2 for each student.

• Group the result by student name to get the second highest marks for each student.

The .live() method attaches an event handler to the current and future elements, while .delegate() attaches an event handler to a parent element.

• The .live() method is deprecated in newer versions of jQuery.

• The .delegate() method is preferred over .live() for performance reasons.

• Both methods are used to handle events for dynamically added elements.

• Example: $(document).live('click', 'button', function() { ... });

• Example:...read more

Chaining in jQuery allows multiple methods to be called on a single element in a single line of code.

• Chaining simplifies code and improves readability.

• Each method in the chain operates on the result of the previous method.

• The chain ends with a method that does not return a jQuery object.

• Example: $('div').addClass('highlight').fadeOut();

A callback function is a function that is passed as an argument to another function and is executed later.

• Callback functions are commonly used in event-driven programming.

• They allow asynchronous execution of code.

• Callback functions can be used to handle responses from APIs or user interactions.

• They can be anonymous functions or named functions.

• Example: setTimeout(function() { console.log('Hello!'); }, 1000);

The .bind() function in jQuery is used to attach an event handler function to one or more elements.

• It allows you to specify the event type and the function to be executed when the event occurs.

• The .bind() function can be used to bind multiple events to the same element.

• It can also be used to pass additional data to the event handler function.

• The .bind() function is deprecated in jQuery version 3.0 and above. It is reco

The angle between the hour and minute hands of a clock can be calculated using a formula.

• The hour hand moves 30 degrees per hour and 0.5 degrees per minute.

• The minute hand moves 6 degrees per minute.

• Calculate the angle between the two hands using the formula: |30H - 11M/2|, where H is the hour and M is the minute.

Yes, it is possible to create a slideshow without using JavaScript.

• Use CSS animations and transitions to create the slideshow.

• Use HTML and CSS to structure and style the slideshow.

• Utilize keyframe animations to create the slide transitions.

• Use radio buttons or checkboxes to control the slideshow navigation.

• Apply the :target pseudo-class to create a simple slideshow without JavaScript.

The men can take turns riding the scooter, allowing them to reach point B faster.

• The men can form a queue and take turns riding the scooter.

• The person riding the scooter can drop it off at a certain point and the next person can pick it up.

• The scooter can be passed along the line of men until everyone reaches point B.