Interview experience of Baidu Mobile Cloud wearable Department of Netizens

1 sides

• Objective C Runtime library:objective C's Object model, block's underlying implementation structure, message sending, message forwarding, these need to be behind the C-layer description, memory management.
• Core data: An operation that handles large amounts of data synchronization in multiple threads.
• Multithreading: When to deal with multi-threading, several ways, pros and cons.
• Delegate, NOTIFICATION,KVO, other advantages and disadvantages

Runtime has a little cross-examine, category,method implementation mechanism, class loading process. 1 side overall feeling good, 40 minutes less, feel the answer can also. Be told to two sides in a moment.

2 sides

Two sides of the time is very long, almost 3 hours, the direct face to get off work. The main question of 1 is the knowledge point. 2 asked the main survey is the ability to design solutions, in addition to assist the way to examine the depth and breadth, the answer process needs to list the specific examples, the program needs to be detailed to the specific key function name, method. In addition, we examine the understanding of design patterns, and finally test the algorithm. Because the time is too long, here are some important questions to note.

1. Design a progress bar solution, cross-examine to Core Graphic, Cgpath, Masklayer.
2. Design a popup view is pressed to Keywindow, UIWindow layer, UIView hierarchy.
3. The difference between delegate, Notification and Kvo is analyzed from the angle of design pattern. Asked to write their own library and open source projects to use which design patterns, why use, what are the advantages and disadvantages, can now be improved.
4. As a matter of question 3, design a scheme to detect KVO synchronous asynchronous problems. The differences between Willchange and Didchange were then asked if there was a similar situation elsewhere and were asked to Falut object in core Data.
5. This is the question 4 of the cross-examine, design a KVO system.
6. Multithreading, when to use the multithreading scheme, and why. Ask the system what else is running in the background thread, be asked to view life cycle, iOS6 after the different and memory management.
7. Multithreading often encountered problems, cross-examine to deadlock, priority rollover, thread pool and so on.
8. Baidu has an billion-tier app that needs to count user behavior in the log system. Do not use the database, just use ordinary files, design a system. is pressed into the memory-mapped file. This problem is a server problem, I said I have never done, the answer is very blind.

The algorithm tested 2. One is how to find the intersection of 2 sets. The other is to find the same number in tens of billions of data and the number of occurrences.

Finally, I added a few minor questions.

• How you feel about wearable devices
• If I get into this team, I'm going to do that thing myself.
• Why entrepreneurship, your own future planning

One will be told 3 sides, but because it is too late, about the next afternoon 3 side.

3 Sides

3 sides of the time and 1 face almost 40 minutes, asked a few questions, mainly to examine the spiritual level of things.

• Why do Windows Mobile
• How to change iOS
• Why Baidu
• Why iphone can be successful and those that attract you
• How to view AppStore's current ecological circle

That's what he said, the difficulties the team encountered and the plans of the 14 team. At last he gave me 2 comments, I think it is quite right.

• The choice was deliberate.
• Ambitious, wanna make a Difference

Interestingly, he said he also wanna make a difference.

Summarize

Overall is quite awkward, almost all of the knowledge points are 1, 2 years ago accumulated, 13 years of accumulation of things basically no, are some virtual things. 2 side is very good, exposed himself a lot of problems, design patterns that part of the almost no concept.

At last

Interview through, I personally think 2 side of my problem in thinking about design patterns, and in addition to the window hierarchy there are insufficient. Design KVO above on the didchange above considered insufficient. These were all laid bare on the spot. One concern was that the core Animation was not asked during the interview. This is still my favorite part. Anyway personally like to ask the way, it is easy to examine the depth and breadth of understanding.

The whole interview was a great harvest and found a lot of deficiencies. Another 1, 2 face interview Topic personally feel also good. Here to share with you.

Interview experience of Baidu Mobile Cloud wearable Department of Netizens