I just finished a complete round recently Microsoft interview process, from the initial overseas application to the final offer, took about two months. In this article, while my memory is still clear, I will sort out the OA + VO timeline, question ideas, and some real-life experiences from the Microsoft question bank, as a reference for students who are preparing for Microsoft/Big Tech interviews.
Timeline
- 11/21: Submit resume
- 12/15:Received OA
- 1/8:Receive VO notification
- 1/21: VO (basically every round) Half BQ + half Coding)
- 1/25: Offer available
Microsoft OA experience
OA is completed remotely on the HackerRank platform, with a total of two coding steps. Strictly speaking, it is not Hard. If you prepare the real questions in advance, you can still do it.
Coding 1: Find the unique string with difference pattern
Question: Given a list of equal-length uppercase letter strings, it is necessary to calculate the "difference sequence of adjacent characters in the alphabet" for each string (for example B→A = -1,C→A = -2). Except for one string, the difference patterns of the rest of the strings are exactly the same. It is required to find and return the string with the only different pattern.
The essence of this question is a typical pattern classification problem. Directly map each string into a difference array (or convert it into a string as a key), and then use a hash table to count the number of occurrences. Finally, find the key that appears only once and return the corresponding original string. The time complexity is close to O(n), which is a very standard hashmap application problem. If you have covered models such as "string feature mapping" in your usual practice, you can basically get AC quickly.
Coding 2: Mark the diameter endpoints of the tree (Special Nodes)
Question: Given a tree, define: diameter = the number of edges of the longest path in the tree. If a node is the endpoint of any diameter path, the node is special. It is required to return a length of Tree_nodes A binary array of: the i-th bit is 1, indicating that the node is special, otherwise it is 0.
The standard solution can be done using cubic BFS/DFS:
- Starting from any node, find the farthest point A
- Start again from A and find the furthest point B →The distance from A-B is the diameter of the entire tree
Finally, based on the distance information, mark all nodes that may become diameter endpoints. If you have mastered this type of question, the recognition speed of this question will be very fast; but if you have not, the on-site derivation may take a lot of time.
How to prepare efficiently for large factory OA?
If you have recently received an OA from Microsoft or other major manufacturers, it is recommended that you try to familiarize yourself with these high-frequency routines in advance. We have compiled a lot of real question banks and interview trends here. If you need specific questions or preparation directions, you can contact us directly.
Need OA assist / Coding support students can also directly consult. It is suitable for mainstream platforms such as HackerRank and Codesignal to ensure that all test cases pass; the risk will be much smaller before entering the game if you are not sure.
