Some Telephone Interview Questions for C++/C# Software Enginners

interview

• What is a Garbage Collector in C# (what does it do).
• Are the objects automatically GC-ed in C#? If not, why/how?
• Are the structs automatically GC-ed in C#?
• Tell me the difference between stack and heap (memory management)
• What is a virtual destructor in C++?
• How do you run two methods in parallel in C#?
• If two methods both increment a variable, is there a problem (is the value higher or lower) and how to fix it?
• How do you implement a function that takes a byte value and return true if its most-significant-bit is set?
• What is the difference between as and is in C#?

Some Answers

You can use Parallel.Invoke or Task.Factory.StartNew and Task.WaitAll to run two methods in parallel.

structs are value-types so they are automatically GC-ed in C#.

Primitive data types like int live in stack while objects are normally in heap.

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inline bool check(byte v) {
  return v & 0b10000000; 
}

inline bool check(byte v) {
  return v & 0b10000000; 
}

You need to lock the variables when multiple threads write to them at the same time – race conditions.

–EOF (The Ultimate Computing & Technology Blog) —