visitor.h:6:  private: should be indented +1 space inside class BfsVisitor  [whitespace/indent] [3]
visitor.h:8:  public: should be indented +1 space inside class BfsVisitor  [whitespace/indent] [3]
visitor.h:8:  "public:" should be preceded by a blank line  [whitespace/blank_line] [3]
visitor.h:35:  Could not find a newline character at the end of the file.  [whitespace/ending_newline] [5]
Done processing visitor.h
Total errors found: 4