自定义一个结构体复数complex,包含实部与虚部.重载减法运算函数,对实部和虚部分别进行减运算,在主函数中分别调用对整

#include
using namespace std;
struct complex
{
double r;
double i;
};
complex operator - (complex a,complex b)
{
complex sum;
sum.r = a.r - b.r;
sum.i = a.i - b.i;
return sum;
}
void out(complex a)
{
cout