c++ - what does default constructor do when it's empty? -

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i wonder if explain default ctor after memory allocated, how initializes allocated memory?

i don't know languange asked question for, try answer anyway c++ , java

in c++, :

  • leaves built-in types (int, float, pointers, etc.) uninitialized value
  • calls default constructor on class members

in java, think class members initialized default value (0 or null).


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