8000+ Software Developer Interview Questions and Answers

Demonstrate multilevel inheritance with classes GrandFather, Father, and Son with specific attributes and methods.

• Create a class GrandFather with a parameterized constructor and attribute grandFatherName.

• Create a class Father inheriting from GrandFather with an additional attribute fatherName.

• Create a class Son inheriting from Father with an additional attribute sonName and a method printName to display all names in a specific format.

• Ensure constructors initialize attributes ...read more

Rearrange array elements based on their differences from a given integer.

• Calculate the differences between each element and the given integer.

• Sort the elements based on their differences while maintaining the original order for elements with the same difference.

• Implement a function to rearrange the array elements as per the given criteria.

This question asks to find the position of a target integer in a row-wise and column-wise sorted matrix.

• Iterate through each row and column of the matrix

• Compare the target integer with the current element

• If the target integer is found, return the position as {i, j}

• If the target integer is not found, return {-1, -1}

Calculate the number of ways Preeti can purchase items within budget, with at least one item quantity differing.

• Use dynamic programming to calculate the number of ways to purchase items within budget.

• Consider different scenarios where Preeti buys different quantities of each item.

• Return the result modulo 10^9 + 7 to handle large answers.

The problem involves finding the number of ways to tile a 2xN board using 2x1 tiles.

• Use dynamic programming to solve this problem efficiently.

• Define a recursive function to calculate the number of ways to tile the board.

• Consider both horizontal and vertical placements of tiles.

• Implement the function to handle large values of N using modulo arithmetic.

• Example: For N = 4, the number of ways to tile the board is 5.

Find the intersection of two square images represented as trees based on color rules.

• A white node (W) intersects with another white node (W) results in W.

• A black node (B) intersects with another black node (B) results in B.

• A white node (W) intersects with a black node (B) results in W.

• A mixed node (M) will have 4 children representing the intersection of its quadrants.

BFS traversal of an undirected and disconnected graph starting from vertex 0.

• Implement BFS algorithm to traverse the graph starting from vertex 0.

• Use a queue to keep track of visited nodes and their neighbors.

• Ensure the traversal starts from vertex 0 and follows the BFS order.

• Output the BFS traversal sequence for each test case in a separate line.

• Handle disconnected components by checking for unvisited nodes.

• Consider the constraints for the number of vertices and edges in the...read more

Find the minimum number of arrows needed to burst all balloons by shooting arrows from left to right.

• Sort the array in non-decreasing order to make it easier to calculate the minimum number of arrows needed.

• Iterate through the sorted array and count the number of times the height decreases compared to the previous balloon.

• The count of decreases + 1 will give the minimum number of arrows needed to burst all balloons.

• Example: For input N = 5, ARR = [2, 3, 4, 5, 1], the minimum ...read more

Implement a cache with insert, update, and retrieve operations, returning results of retrieve operations in order.

• Create a cache data structure with specified size 'N'.

• Implement insert and update operations based on the given criteria.

• For retrieve operation, return the value associated with the 'U_ID' if present, else return -1.

• Handle cases where the cache is full and least frequently used items need to be removed.

• Return the results of all retrieve operations in the order the...read more

The task is to count the total number of '1' in the binary representation of all numbers from 1 to N.

• Convert each number from 1 to N into its binary representation

• Count the number of '1' bits in each binary representation

• Sum up the counts of '1' bits for all numbers

• Return the sum modulo 1e9+7

Program to check if a given number is a lucky number or not.

• Create a function that takes an integer n as input

• Initialize a variable count to 2

• Loop through the sequence and delete every count-th element

• Repeat the above step until the end of the sequence

• If n is present in the final sequence, return true, else return false

Validate IFSC code based on given rules and return True or False for each test case.

• Check if the code is 11 characters long.

• Verify the first four characters are uppercase alphabets.

• Ensure the fifth character is '0'.

• Validate that the last six characters are alphanumeric.

The problem involves constructing the longest happy string with given constraints on the frequency of 'a', 'b', and 'c'.

• Iterate through the characters 'a', 'b', 'c' in decreasing order of their frequencies

• Append the character with the highest frequency that does not create a substring of 3 same characters

• Repeat until all characters are used up or the string reaches the desired length

Find the maximum sum of a subsequence without choosing adjacent elements in an array.

• Use dynamic programming to keep track of the maximum sum at each index, considering whether to include or exclude the current element.

• At each index, the maximum sum can be either the sum of the current element and the element two positions back, or the sum at the previous index.

• Iterate through the array and update the maximum sum accordingly.

• Example: For input [3, 2, 7, 10], the maximum non-a...read more

Given a permutation of 'N' integers, rearrange the numbers to form the lexicographically next greater permutation.

• Iterate from right to left to find the first element that is smaller than the element to its right.

• Swap this element with the smallest element to its right that is greater than it.

• Reverse the elements to the right of the swapped element to get the lexicographically next greater permutation.

• If no such element is found in step 1, then the permutation is already the ...read more

Calculate the earliest day on which Ninja can buy all candies with special offers.

• Iterate through each day and check if any special offer is available for candies Ninja wants to buy

• Keep track of the minimum day on which Ninja can buy all candies

• Consider both regular price and sale price of candies

The oldest pirate proposes to keep 98 coins for himself and give 1 coin to each of the other pirates.

• The oldest pirate will propose to keep the majority of the coins for himself to ensure the vote passes.

• The other pirates will vote in favor of the proposal to avoid being thrown overboard.

• The proposed distribution will be 98 coins for the oldest pirate and 1 coin for each of the other pirates.

Given a binary tree, a target node, and an integer K, find all nodes at distance K from the target node.

• Traverse the binary tree to find the target node.

• Use BFS to traverse the tree from the target node to nodes at distance K.

• Keep track of the distance while traversing the tree.

• Return the values of nodes at distance K in any order.

Check if a string is formed by interleaving two other strings.

• Iterate through characters of A, B, and C simultaneously to check if C is formed by interleaving A and B.

• Use dynamic programming to efficiently solve the problem.

• Handle edge cases like empty strings or unequal lengths of A, B, and C.

• Example: A = 'aab', B = 'abc', C = 'aaabbc' should return True.

Find the minimum number of dice throws required to reach the last cell on a 'Snake and Ladder' board.

• Start from the bottom left cell and move according to dice outcomes (1-6).

• Utilize snakes and ladders to reach the last cell faster.

• Keep track of the minimum number of throws required to reach the last cell.

• If unreachable, return -1 as output.

The goal is to determine the maximum profit that can be achieved by buying and selling stocks on different days.

• Iterate through the stock prices and buy on days when the price is lower than the next day, and sell on days when the price is higher than the next day.

• Calculate the profit by summing up the differences between buying and selling prices.

• Repeat the process for each test case and output the maximum profit achieved.

• Example: For prices [7, 1, 5, 3, 6, 4], buy on day 2 a...read more

The problem involves selecting the smallest character from the first 'K' characters of a string and appending it to a new string until the original string is empty.

• Iterate through the string, selecting the smallest character from the first 'K' characters each time.

• Remove the selected character from the original string and append it to the new string.

• If fewer than 'K' characters remain, sort and append them in order.

• Repeat the process until the original string is empty.

Software is a collection of data, programs, procedures, instructions, and documentation that perform tasks on a computer system.

• Software is essential for computers to be useful.

• It includes programs, libraries, and non-executable data.

• Software and hardware work together to enable modern computing systems.

• Examples of software include operating systems, web browsers, and games.

The task is to find the Nth Fibonacci number using matrix exponentiation.

• Use matrix exponentiation to efficiently calculate the Nth Fibonacci number

• Return the answer modulo 10^9 + 7 to handle large numbers

• Implement the function to solve the problem

• The Fibonacci sequence starts with 1, 1, so F(1) = F(2) = 1

• The time complexity can be improved to better than O(N) using matrix exponentiation

Count the number of even or odd numbers in a range of an array based on given queries.

• Create an array to store the input numbers.

• Iterate through the queries and update or count even/odd numbers based on the query type.

• Output the count of even or odd numbers for each query of type 1 or 2.

Develop a function to remove all instances of a given character from a string.

• Iterate through the string character by character and exclude the specified character while constructing the new string.

• Use a StringBuilder or similar data structure for efficient string manipulation.

• Handle edge cases such as empty string or character not found in the input string.

• Ensure the function runs in O(N) time complexity where N is the length of the input string.

Selection Sort Algorithm sorts an array by repeatedly finding the minimum element and placing it at the beginning of the unsorted part.

• Iterate through the array to find the minimum element and swap it with the first unsorted element.

• Repeat this process for each element in the array until it is fully sorted.

• Time complexity of Selection Sort is O(n^2) making it inefficient for large arrays.