Avalara Technologies Software Developer Interview Questions and Answers

Find the minimum number of taps needed to water the entire garden using given tap ranges.

• Iterate over each tap and find the maximum range it can cover.

• Sort the taps based on their starting position and ending position.

• Use a greedy approach to select the taps that cover the maximum range possible.

• If any part of the garden remains uncovered, return -1.

DFS traversal problem on an undirected and disconnected graph to find connected components.

• Perform Depth First Search (DFS) on the graph to find connected components.

• Use a visited array to keep track of visited vertices.

• Iterate through all vertices and perform DFS on unvisited vertices to find connected components.

• Print the number of connected components and list vertices in each component in ascending order.

Implement a queue using stacks following FIFO principle.

• Use two stacks to simulate a queue - one for enqueueing and one for dequeueing.

• For enqueuing, simply push elements onto the stack.

• For dequeuing, if the dequeue stack is empty, transfer all elements from enqueue stack to dequeue stack.

• Peek operation can be done by checking the top element of the dequeue stack.

• Check if the queue is empty by verifying if both stacks are empty.

Return all subsets of an array that sum to a given integer K.

• Use recursion to generate all possible subsets of the array.

• Keep track of the current subset and its sum while traversing the array.

• If the sum of the subset equals K, add it to the result.

• Sort the elements in each subset to ensure increasing order of index.

• Handle duplicate elements in the array appropriately.

Partition a string into palindromes and return all possible configurations.

• Use backtracking to generate all possible palindrome partitions of the string.

• Check if each substring is a palindrome before adding it to the partition.

• Return all valid partitions as an array of strings.

OOPs concepts refer to Object-Oriented Programming concepts which include Inheritance, Encapsulation, Polymorphism, and Abstraction.

• Inheritance: Allows a class to inherit properties and behavior from another class.

• Encapsulation: Bundling data and methods that operate on the data into a single unit.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details and showing only the necessary features.