operator!= function template Checks inequality

template<typename T>
  bool operator!=(const complex<T>&, const complex<T>&);
template<typename T>
  bool operator!=(const complex<T>&, const T&);
template<typename T>
  bool operator!=(const T&, const complex<T>&);

The != operator returns true if the real or imaginary parts are not equal. If either operand is of type T, the parameter is interpreted as the real part, with an imaginary part of T( ) or 0.