What's a wrong performance decision when choosing objects to handle critical parts for an algorithm, when the order of data is not important?
Choose a List instead of a HashMap/HashSet.
What's a probable expensive mistake when passing variables to functions, not very obvious for a beginner C++ developer?
Passing by value instead of passing by reference.
What's the most common mistake of a developer new in the C world?
Declare a string (array of chars) of the exact size, not taking into account the null terminator.