ADTs de 1ª ordem: números complexos

Interface

 #ifndef __COMPLEX_H__
 #define __COMPLEX_H__
 
 typedef struct complex *Complex;
 
 Complex COMPLEXinit(double, double);
 double  COMPLEXre(Complex);
 double  COMPLEXim(Complex);
 Complex COMPLEXmult(Complex, Complex);
 
 #endif

Implementação

 #include <stdlib.h>
 #include "COMPLEX.h"
 
 struct complex { double re, im; };
 
 Complex COMPLEXinit(double re, double im) {
   Complex t = (Complex)malloc(sizeof(*t));
   t->re = re; t->im = im; return t;
 }
 
 double COMPLEXre(Complex c) { return c->re; }
 double COMPLEXim(Complex c) { return c->im; }
 
 Complex COMPLEXmult(Complex a, Complex b) {
   return COMPLEXinit(COMPLEXre(a) * COMPLEXre(b) – COMPLEXim(a) * COMPLEXim(b),
                      COMPLEXre(a) * COMPLEXre(b) + COMPLEXim(b) * COMPLEXim(b));
 }