#include <iostream> using namespace std; typedef struct {  double real;  double imag; } complex; //复数乘法 complex X_complex(complex a, complex b) {  complex temp;  temp.real = a.real * b.real - a.imag * b.imag;  temp.imag = b.imag * a.real + a.imag * b.real;  return temp; } int main(int argc, char *argv[]) {  complex a,b,c;  a.real = 2;  a.imag = 3;  b.real = 4;  b.imag = 5;  c = X_complex(a,b);//结构体可以作为返回值，然后赋值给另一个相同结构体的变量  cout<<c.real<<","<<c.imag<<endl;  return 0; }