10+ Interview Questions and Answers

The difference is that 'int arr[5]' creates an array on the stack, while 'malloc(5*sizeof(int))' allocates memory on the heap.

• int arr[5] creates an array of 5 integers on the stack, which is a fixed-size memory allocation.

• malloc(5*sizeof(int)) dynamically allocates memory on the heap, allowing for variable-size memory allocation.

• The memory allocated with malloc must be explicitly freed with free() to avoid memory leaks.

Data structures are fundamental concepts in software engineering that organize and store data efficiently.

• Arrays: Simple and efficient for storing and accessing elements.

• Linked Lists: Dynamic and flexible, efficient for insertion and deletion.

• Stacks: LIFO structure, useful for managing function calls and undo operations.

• Queues: FIFO structure, ideal for managing tasks and scheduling.

• Trees: Hierarchical structure, used for organizing data like file systems or search algorithms...read more

Reverse a linked list without using extra memory

• Iterate through the linked list and change the next pointers to reverse the list

• Use three pointers - prev, current, and next - to keep track of the reversed list

• Start with prev and current pointing to null and the head of the linked list respectively

• While traversing the list, update the next pointer of the current node to point to the previous node

• Move prev and current pointers one step forward

• Repeat until the end of the list is...read more

Find elements in array that sum up to given number

• Use a nested loop to iterate through each pair of elements in the array

• Check if the sum of the pair equals the given number

• Return the pair of elements if found, otherwise continue iterating

Program to reverse an integer

• Convert the integer to a string

• Reverse the string

• Convert the reversed string back to an integer

IPC mechanisms are used for inter-process communication in software development.

• IPC mechanisms allow processes to communicate with each other, either on the same machine or across a network.

• Common IPC mechanisms include pipes, message queues, shared memory, sockets, and signals.

• Examples of IPC mechanisms include using sockets for network communication between client and server applications, or using shared memory for communication between processes on the same machine.

Socket communication is a method of communication between two processes on a network using sockets.

• Socket communication involves a client and a server communicating over a network.

• It uses TCP or UDP protocols to establish a connection.

• Data is exchanged through sockets using read and write operations.

• Sockets can be used for various applications like web browsing, email, and file transfer.

I2C and SPI are serial communication protocols used for connecting microcontrollers to peripherals.

• I2C (Inter-Integrated Circuit) is a synchronous, multi-master, multi-slave, packet-switched protocol commonly used for communication between integrated circuits.

• SPI (Serial Peripheral Interface) is a synchronous, full-duplex, master-slave communication protocol commonly used for communication between microcontrollers and peripheral devices.

• I2C uses two wires (SDA and SCL) for co...read more

Implement a shopping cart system using data structures and algorithms.

• Use a data structure like a hash map to store items and their quantities in the cart.

• Implement functions to add, remove, and update items in the cart.

• Consider implementing functions to calculate total price, apply discounts, and handle checkout process.

Binary search is a search algorithm that finds the position of a target value within a sorted array.

• Divide the array into two halves and compare the target value with the middle element.

• If the target value is equal to the middle element, return the index.

• If the target value is less than the middle element, recursively search the left half.

• If the target value is greater than the middle element, recursively search the right half.

Implement a custom hashmap in Java

• Create a class to represent the hashmap

• Use an array to store the key-value pairs

• Implement methods for put, get, and remove operations

Find the number of subarrays whose sum is divisible by K.

• Use prefix sum technique to calculate the sum of subarrays efficiently.

• Keep track of the remainders of prefix sums when divided by K.

• Use a hashmap to store the count of each remainder.

• For each prefix sum, check how many previous prefix sums have the same remainder.

• Add the count of subarrays with the same remainder to the total count.

Arrays are a collection of strings in programming used to store multiple values under a single variable name.

• Arrays are declared using square brackets []

• Each element in an array is accessed by its index, starting from 0

• Example: var fruits = ['apple', 'banana', 'orange']

Trees in neet code refer to the implementation of tree data structures in coding challenges on the platform NeetCode.

• Trees are a common data structure used in coding challenges to represent hierarchical relationships between data.

• Common tree operations include traversal (inorder, preorder, postorder), insertion, deletion, and searching.

• Examples of tree-related coding challenges on NeetCode include implementing a binary search tree, finding the lowest common ancestor of two no...read more