#include <iostream>
using namespace std;
struct complex
{
    double Re;
    double Im;
};
void vvod_complex(complex *x);
void vivod_complex(complex *x);
void plus(complex *x, complex *y, complex *z);
void minus(complex *x, complex *y, complex *z);
int main()
{
    complex a,b,c;
    vvod_complex(&a); 
    vvod_complex(&b);
    cout<<"a="; vivod_complex(&a);
    cout<<"b="; vivod_complex(&b);
    plus(&a,&b,&c);
    cout<<"a+b="; vivod_complex(&c);
    minus(&a,&b,&c);
    cout<<"a-b="; vivod_complex(&c);
    system("pause");
}
void minus(complex *x, complex *y, complex *z)
{
    z->Re=x->Re - y->Re;
    z->Im=x->Im - y->Im;
}
void plus(complex *x, complex *y, complex *z)
{
    z->Re=x->Re + y->Re;
    z->Im=x->Im + y->Im;
}
void vvod_complex(complex *x)
{
    cin>>x->Re>>x->Im;
}
void vivod_complex(complex *x)
{
    cout<<x->Re;
    if (x->Im>0 ) cout <<"+";
    cout<<x->Im<<"i"<<endl;
}