/* 
 * cpx.c - implementation of a simple complex number package
 * version 2: struct pointer parameters & string dynamic allocation
 * CSE 413 demo 11/06 HP
 */

#include <stdio.h>
#include <stdlib.h>
#include "cpx.h"

/* number of characters in dynamic string result of cpx2str (including '\0' */
#define STRCHRS 100

/* return a complex number with real part = x and imaginary = y */
Complex mk_complex(double x, double y) {
  Complex result;
  result.re = x;
  result.im = y;
  return result;
}

/* return the sum of complex numbers c and d */
Complex cpx_add(Complex* c, Complex* d) {
  Complex result;
/*result =  mk_complex((*c).re + (*d).re, (*c).im + (*d).im); */
  result =  mk_complex(c->re + d->re, c->im + d->im);
  return result;
}

/* return a representation of c as re+im i in a newly allocated string */
char* cpx2str(Complex* c) {
  char* result;
  result = (char *)malloc(STRCHRS);
  sprintf(result, "%g+%gi", c->re, c->im);
  return result;
}