How to Overload the \'<<\' Operator as a Friend for Template Class \'Pair\'?

Overloading Operator '<<' as Friend for Template Class 'Pair'

When attempting to overload the '<<' operator as a friend to the template class 'Pair,' users may encounter a compiler warning. This message alerts the programmer to a non-template function declaration issue.

To properly overload the operator, the friend declaration should be modified as follows:

friend ostream& operator<< <> (ostream&, Pair&);
By leaving the template arguments empty within the '<>', the compiler can infer the parameter list to identify the specific specialization of the template.
To eliminate the warning entirely, the declaration of 'operator<<' should precede the template definition of 'Pair', resembling the following structure:
template  class Pair;

template 
ostream& operator<<(ostream& out, Pair& v);

// Template definition of 'Pair'

By adhering to this revised syntax, the compiler can recognize the friend declaration as a specialization of the template and overload the '<<' operator accordingly.
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