PubMatic Big Data Engineer Interview Questions, Process, and Tips

Count pairs in an array that sum up to a target value.

• Iterate through the array and store the frequency of each element in a hashmap.

• For each element, check if the difference between the target and the element exists in the hashmap.

• Increment the count of pairs if the difference is found in the hashmap.

Binary search can be used to solve moderate problems of arrays that are first increasing and then decreasing.

• Use binary search to find the peak element in the array, which marks the transition from increasing to decreasing.

• Divide the array into two parts based on the peak element and apply binary search on each part separately.

• Handle edge cases such as when the array is strictly increasing or strictly decreasing.

• Exampl

Design a system for a web surfing utility

• Use a web crawler to gather data from websites

• Implement a search engine to retrieve relevant information

• Utilize a recommendation system to suggest related content

• Include user authentication and personalized settings

• Ensure scalability and performance for handling large amounts of data

Find the smallest subarray in an array that has a given target sum.

• Use a sliding window approach to find the subarray with the target sum.

• Keep track of the current sum of elements in the window and adjust the window size accordingly.

• Start with a window of size 1 and expand it until the sum is greater than or equal to the target sum.

• Shrink the window from the left side while updating the smallest subarray length until t