实验9-4 计算两个复数之积 (15 分)

本题要求实现一个计算复数之积的简单函数。

函数接口定义：

struct complex multiply(struct complex x, struct complex y);

其中struct complex是复数结构体，其定义如下：

struct complex{
    int real;
    int imag;
};

裁判测试程序样例：

#include 

struct complex{
    int real;
    int imag;
};

struct complex multiply(struct complex x, struct complex y);

int main()
{
    struct complex product, x, y;

    scanf("%d%d%d%d", &x.real, &x.imag, &y.real, &y.imag);
    product = multiply(x, y);
    printf("(%d+%di) * (%d+%di) = %d + %din", 
            x.real, x.imag, y.real, y.imag, product.real, product.imag);

    return 0;
}

输入样例：

3 4 5 6

结尾无空行

输出样例：

(3+4i) * (5+6i) = -9 + 38i

结尾无空行

struct complex multiply(struct complex x, struct complex y) //返回了一个结构multiply
{
    struct complex multiply;
    multiply.real = x.real * y.real - x.imag * y.imag;
    multiply.imag = x.imag * y.real + x.real * y.imag;
    return multiply;
}