фывфа

#include <iostream>
using namespace std;

class vec {
friend class arr_vec;
private: double x, y, z;
public: friend vec operator+ (vec, vec);
friend vec operator* (vec, double);
friend vec operator* (double, vec);
friend vec toVec(double x, double y, double z);
};

vec toVec (double x, double y, double z) {
vec v;
v.x=x;
v.y=y;
v.z=z;
return v;
}
vec operator+ (vec c, vec d) {
return toVec(c.x+d.x, c.y+d.y, c.z+d.z);}

vec operator* (vec c, double d) {
return toVec(c.x*d, c.y*d, c.z*d);}

vec operator* (double c, vec d) {
return toVec(c*d.x, c*d.y, c*d.z);}

class arr_vec {
private: double *x, *y, *z;
int n;
public: arr_vec(int);
~arr_vec();
void set(int, vec);
vec operator[] (int) const;
void operator=(const arr_vec&);
friend arr_vec operator+ (const arr_vec&, const arr_vec&);
friend arr_vec operator* (double, const arr_vec&);
friend arr_vec operator* (const arr_vec&, double);
void show();
};
void arr_vec::operator =(const arr_vec& A) {
    n=A.n;
    x= new double [n];
    y=new double[n];
    z=new double [n];
    for(int i=0; i<n; i++) {x[i]=A.x[i]; y[i]=A.y[i]; z[i]=A.z[i];}
}

arr_vec::arr_vec(int N) {
n=N;
x=new double[n];
y=new double[n];
z=new double[n];
for(int i=0; i<n; i++) {x[i]=y[i]=z[i]=1;}
}
arr_vec::~arr_vec() {
delete[]x;
delete[]y;
delete[]z;
}
void arr_vec::set(int N, vec vvv) {
if (n<N) return;
x[N]=vvv.x;
y[N]=vvv.y;
z[N]=vvv.z;
}
vec arr_vec::operator [](int N) const {
return toVec(x[N], y[N], z[N]);
}
arr_vec operator+ (const arr_vec& c, const arr_vec& d) {
arr_vec *e;
e=new arr_vec(c.n);
for(int i=0; i<e->n; i++) e->set(i, c[i]+d[i]);
return *e;
}
arr_vec operator* (double c, const arr_vec& d) {
arr_vec *e;
e=new arr_vec(d.n);
for (int i=0; i<e->n; i++) e->set(i, c*d[i]);
return *e;
}
arr_vec operator* (const arr_vec& c, double d) {
arr_vec *e;
e=new arr_vec(c.n);
for (int i=0; i<e->n; i++) e->set(i, c[i]*d);
return *e;
}
void arr_vec::show() {
cout<<endl<<"X: ";
for(int i=0; i<n; i++) cout<<x[i]<<"\t";
cout<<endl<<"Y: ";
for(int i=0; i<n; i++) cout<<y[i]<<"\t";
cout<<endl<<"Z: ";
for(int i=0; i<n; i++) cout<<z[i]<<"\t";
cout<<endl;
}

int main() {
arr_vec c(2), d(2);
vec e, f;
e=toVec(1,2,3);
f=toVec(4,5,6);
c.set(0, e);
c.show();
c=c+c;
c.show();
}