30+ Reliable Software Systems Private Limited Interview Questions and Answers

Reconstruct original sequence of cards given a specific sequence of cards placed on table.

• The last card placed on the table must be 10.

• The second last card placed on the table must be 5 or 6.

• The first card placed on the table must be either 1 or 2.

• Use trial and error method to reconstruct the original sequence.

Java function to return subnet mask of IP and URL after www.

• Read the file and store IP addresses and URLs in separate arrays

• Use regex to extract subnet mask from IP address

• Use substring to extract URL after www.

• Return subnet mask and URL as separate strings

For Snapdeal's shoe section, I would design a DBMS with separate entities for Sports and Casual Shoes.

• Create a main entity for shoes with attributes like brand, size, color, etc.

• Create separate entities for Sports and Casual Shoes with attributes specific to each category.

• Link the Sports and Casual Shoe entities to the main Shoe entity using a foreign key.

• Use indexing and normalization techniques to optimize performance and reduce redundancy.

• Consider implementing a search fea...read more

Burn one rope from both ends and the other rope from one end.

• Light one rope from both ends and the other rope from one end.

• When the first rope burns completely, 30 minutes have passed.

• Then, immediately light the other end of the second rope.

• When the second rope burns completely, 15 more minutes have passed.

• Total time elapsed is 45 minutes.

Merge two sorted arrays into one sorted array of larger size

• Create a new array of size m+n

• Compare the last elements of both arrays and insert the larger one at the end of the new array

• Repeat until all elements are merged

• If any elements are left in the smaller array, insert them at the beginning of the new array

• Time complexity: O(m+n)

• Example: arr1=[1,3,5,7,0,0,0], arr2=[2,4,6], output=[1,2,3,4,5,6,7]

The question asks to find the count of words in a dictionary that can be formed by a given number.

• Iterate through each word in the dictionary

• Check if the characters in the word can be formed using the given number

• Increment the count if the word can be formed

DNS servers translate domain names into IP addresses to enable communication between devices on the internet.

• DNS servers act as a phone book for the internet, translating domain names into IP addresses.

• When a user types a domain name into their browser, the browser sends a request to a DNS server to resolve the domain name into an IP address.

• DNS servers operate in a hierarchical system, with root servers at the top, followed by top-level domain servers, and then authoritative...read more

Finding lowest common ancestor of two nodes in binary tree

• Traverse the tree from root to both nodes and store the paths in separate arrays

• Compare the paths to find the last common node

• Return the last common node as the lowest common ancestor

• Use recursion to traverse the tree efficiently

Algorithm to find LCM of all numbers from 1 to n and its time complexity

• Find prime factors of all numbers from 1 to n

• For each prime factor, find the highest power it appears in any number from 1 to n

• Multiply all prime factors raised to their highest power to get LCM

• Time complexity: O(n*log(log(n)))

The number is 7744.

• The number must end in 00 or 44.

• The square root of the number must be a whole number.

• The only possible number is 7744.

To find the length of non-looped linked list, we need to traverse the list and count the number of nodes.

• Traverse the linked list using a pointer and count the number of nodes until the end of the list is reached.

• If a loop is encountered, break out of the loop and continue counting until the end of the list.

• Return the count as the length of the non-looped linked list.

A program to check if a number is a palindrome or not.

• Convert the number to a string

• Reverse the string

• Compare the original and reversed string

• If they are the same, the number is a palindrome

Inner join returns only the matching rows between two tables, while outer join returns all rows from one table and matching rows from the other.

• Inner join combines rows from two tables based on a matching column.

• Outer join returns all rows from one table and matching rows from the other.

• Left outer join returns all rows from the left table and matching rows from the right table.

• Right outer join returns all rows from the right table and matching rows from the left table.

• Full ou...read more

To find the merging point of two linked lists

• Traverse both linked lists and find their lengths

• Move the pointer of the longer list by the difference in lengths

• Traverse both lists simultaneously until they meet at the merging point

NoSQL databases are flexible, scalable, and can handle large amounts of unstructured data.

• NoSQL databases are schema-less, allowing for easy and flexible data modeling.

• They can handle large amounts of unstructured data, making them suitable for big data applications.

• NoSQL databases are highly scalable and can easily handle high traffic and large user bases.

• They provide horizontal scalability by distributing data across multiple servers.

• NoSQL databases are often used in real-t...read more

The number of rectangles in an MxN matrix can be calculated using a formula.

• The formula is (M * (M + 1) * N * (N + 1)) / 4

• The matrix can be divided into smaller sub-matrices to count the rectangles

• The number of rectangles can also be calculated by counting all possible pairs of rows and columns

To find square root of a number, use Math.sqrt() function in JavaScript.

• Use Math.sqrt() function in JavaScript to find square root of a number.

• For example, Math.sqrt(16) will return 4.

• If the number is negative, Math.sqrt() will return NaN.

Reverse a linked list iteratively

• Create three pointers: prev, curr, and next

• Initialize prev to null and curr to head

• Loop through the list and set next to curr's next node

• Set curr's next node to prev

• Move prev and curr one step forward

• Return prev as the new head