3) HugeInteger multiply(const HugeInteger& h): Returns a new HugeInteger representing the product of this HugeInteger and h. This method should not be implemented as repeated addition (calculate m*n by adding m, n time) since its too slow. Also, the asymptotic time complexity of your implementation of the multiplication of two integers of at most n digits is o(n2) (i.e., subquadratic). Please take into consideration all the possible sign case for both the hugeintegers and write the code in c++.