Microsoft visited my university during a career fair, where I submitted my resume. Two weeks later, they called me for an on-campus interview. The interview was short, lasting approximately 30 minutes, and I was asked one simple coding question (Rotate array from the middle) and one system design question (Design Amazon.com). I fumbled a little on the system design part, as I wasn't well-prepared for it.

My recruiter sent an email stating I was selected, but the interview slots had already been filled (in November). I followed up in January and fortunately, they called me for on-site interviews.

On-site Interview 1: Given an array A, find the count of ordered pairs. An ordered pair is defined as any number A[j] such that A[j] > A[i] and j > i. You have to complete this in optimal time.

Interview 2: Given a 2D matrix containing 0s and 1s, count the number of shapes in the matrix. A shape is represented by adjacently connected 1s, either horizontally or vertically, but not diagonally.

Interview 3: Design a data structure that represents both a stack and a queue, with all operations (pop, push, enqueue, dequeue) performed in constant time. Some behavioral questions were asked during this interview as well (Accomplishments, Why Microsoft?).

Interview 4: Given a 2D matrix with 0s and 1s, find the cost of the shortest path from the top-left to the bottom-right, where 0 and 1 represent each cell's cost.

I couldn't get the offer as I went blank during my fourth round, even though the question wasn't hard. Practice LeetCode and CTCI, and you should be good to go.

Given an array A, find the count of the ordered pairs.

An ordered pair is defined as any number A[j], such that A[j] > A[i] and j > i.

You have to do this in optimal time.