c++ - Recursive pointer function -


i struggling implement method called find_set within class blob. recursive function returns pointer blob object. blob class linked list , function supposed passed blob , recursively traverse blob's parents until arriving @ head of blob list. @ work having recreate components. not copy , pasted version of code, want know how time home.

class blob{  public: int size; int index[2]; char value; blob *parent; blob *find_set(blob* &in_question); };

the necessary elements of blob class understand conundrum.

blob* blob::find_set(blob* &in_question){ if(in_question!=nullptr)    in_question.parent= find_set(&in_question.parent); return in_question; }

i hope have been explicit enough.

so, i'm guessing problem here:

blob* blob::find_set(blob* &in_question){ if(in_question!=nullptr)    in_question.parent= find_set(&in_question.parent); return in_question; }

i'm not quite sure why you're taking reference pointer, here's working version of code:

blob* blob::find_set(blob* in_question){     if(in_question != nullptr)        in_question->parent = find_set(in_question->parent);     return in_question; }
  • accessing members of pointer requires using -> instead of .
  • taking address of in_question->parent yields object of type blob**, not want

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