class Complex { real : number ; img : number ; constructor ( real , img ) { this . real = real ; this . img = img ; } public add ( a ) { return new Complex ( a . real + this . real , a . img + this . img ) ; } public mult ( a ) { return new Complex ( a . real - this . real , a . img - this . img ) ; } public product ( ) { } } export default { Complex } ;