CS202   2- ‹#›
For Example, here is a Class Interface
äclass string {
ä public:
ä string();
ä int length();
ä friend ofstream & operator <<
ä (ofstream &, const string &);
ä friend ifstream & operator >>
ä (ifstream &, string &);
ä private:
ä char str[20];
ä int len;
ä};
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