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

typedef struct {
		double re;
		double im;
} complex;

complex *csum(const complex a, const complex b);
complex *csub(const complex a, const complex b);
complex *cprod(const complex a, const complex b);
complex *cdiv(const complex a, const complex b);

int main(void)
{
	complex a, b, *c;

	a.re = 1.0;
	a.im = 0.0;
	b.re = 0.0;
	b.im = 1.0;
	
	c = csum(a, b);
	printf("c->re=%f, c->im=%f\n", c->re, c->im);
	
	c = csub(a, b);
	printf("c->re=%f, c->im=%f\n", c->re, c->im);

	c = cprod(a, b);
	printf("c->re=%f, c->im=%f\n", c->re, c->im);

	c = cdiv(a, b);
	printf("c->re=%f, c->im=%f\n", c->re, c->im);

	return 0;
}

complex *csum(const complex a, const complex b)
{
	complex *c = (complex *)malloc(sizeof(complex));

	if ( c == NULL){
		printf("メモリの割り当てに失敗しました\n");
		exit(EXIT_FAILURE);
	}

	c->re = a.re + b.re;
	c->im = a.im + b.im;

	return c;
}

complex *csub(const complex a, const complex b)
{
	complex *c = (complex *)malloc(sizeof(complex));

	if ( c == NULL){
		printf("メモリの割り当てに失敗しました\n");
		exit(EXIT_FAILURE);
	}

	c->re = a.re - b.re;
	c->im = a.im - b.im;
}

complex *cprod(const complex a, const complex b)
{
	complex *c = (complex *)malloc(sizeof(complex));

	if ( c == NULL){
		printf("メモリの割り当てに失敗しました\n");
		exit(EXIT_FAILURE);
	}

	c->re = a.re * b.re - a.im * b.im;
	c->im = a.im - b.re + a.im * b.re;
}

complex *cdiv(const complex a, const complex b)
{
	complex *c = (complex *)malloc(sizeof(complex));

	if ( c == NULL){
		printf("メモリの割り当てに失敗しました\n");
		exit(EXIT_FAILURE);
	}

	c->re = (a.re * b.re + a.im * b.im)/(b.re * b.re + b.im * b.im);
	c->im = (b.re - a.im - a.re * b.re)/(b.re * b.re + b.im * b.im);
}