Exercice 22 nombres complexes (structures)

//Exercice 22 nombres complexes (structures) pag.60

#include <iostream>
using namespace std;

struct complexe {
    double x;
    double y;
    };

void affiche (complexe const num);
complexe addition (complexe const a,complexe const b);
complexe soustraction (complexe const a,complexe const b);
complexe multiplication (complexe const a,complexe const b);
complexe division (complexe const a,complexe const b);
int main(){
    complexe a{2,-3};
    complexe b{1,1};
    affiche (addition (a,b));
    affiche (soustraction (a,b));
    affiche (multiplication (a,b));
    affiche (division(a,b));

return 0;
};
//----------------------------------------------------------------------
//----------------------------------------------------------------------
void affiche (complexe const num){
    cout <<'('<<num.x << ","<<num.y<<')'<<endl;
}
//----------------------------------------------------------------------
complexe addition (complexe const a,complexe const b){
    return {a.x+b.x,a.y+b.y};
};
//----------------------------------------------------------------------
complexe soustraction (complexe const a,complexe const b){
    complexe c(b);
    c.x*=-1;
    c.y*=-1;
    return addition(a,c);
}
//----------------------------------------------------------------------
complexe multiplication (complexe const a,complexe const b){
    return {a.x*b.x -a.y*b.y,a.x*b.x+b.y*a.x};
}
//----------------------------------------------------------------------
complexe division (complexe const a,complexe const b){
    return {(a.x*b.x+a.y*b.y)/(b.x*b.x+b.y*b.y), (a.y*b.x-a.x*b.y)/(b.x * b.x +b.y*b.y)};
};