Buatlah program untuk mencari bilangan prima dengan C++

class prima{
int value;
int state;
//fungsi kamu yang sudah
int isprime(long n){
int pstate = 1; //status prima ; 0 bukan prima; 1 prima
for (int i=2; (i<n) && pstate; i++)
{
if (n%i==0) {i=n+1; pstate=0;}
}
return pstate;
}
public:
prima():value(0){};
prima(const int& a):value(x){}
prima(const prima& a){value = a.value;}
protected:
friend ostream& operator << (ostream& o, const prima& a){
value = a.value;
state = isprime(value);
o << (state ? "BUKAN PRIMA" : "PRIMA");
return o;
}
};

void main(){
prima bilangan;
bilangan = 17;
cout << bilangan << endl;
}