SDE - Intern

Step 1: I initially solved the problem using a hash map, where I iterated through the array to count the occurrences of each element and then identified the unique one. This was a brute-force approach.
Step 2: The interviewer asked me to optimize the solution.
Step 3: I then implemented an optimized solution using the XOR operator. The interviewer was satisfied with this approach, and we moved on to the next problem.

Step 1: I solved the problem using a brute-force approach, where I iterated through the array for each element to find the next greater element.
Step 2: The interviewer asked me to optimize the solution.
Step 3: I then implemented an efficient solution using a stack, which reduces the time complexity to O(N). The interviewer was satisfied with this approach, and we moved on to the next problem.
Here one thing happened when I said that I will be using stack, he asked me that how will I implement stack, I reverted that I will be using C++ STL, but we can implement it using Array or using Linked List. So he asked me to do so using array, which I tried but on failing I was allowed to use the library. So you must keep your basics foundation strong.

Step 1: I first conveyed the approach using a hash map to count the frequency of each element.

Step 2: To track the top k frequent elements, I used a priority queue of size k to store pairs of (frequency, number). This helps in efficiently maintaining the elements with the highest frequencies.

Step 3 (Optimization): The optimized solution relies on the hash map for frequency counting, which provides O(N) time complexity for counting. The heap operations for maintaining the top k elements are O(log k), making the overall complexity efficient. I coded this one only and not the brute force approach.

I was familiar with the concept and the logic required to build the component. However, I needed a refresher on the exact syntax. I managed to code the component successfully with the interviewer’s guidance, as I was able to recall the necessary steps while working through it.