Menghitung luas persegi dengan c++ "tugas program modify 3(a) "

#include <iostream>
using namespace std;
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
class persegi{
public:
int s;
int luas(){return(s*s);
}
};
int main(int argc, char** argv) {
persegi x;
cout<<"masukan sisi: ";cin>>x.s;
cout<<"luas persegi: "<<x.luas();
return 0;
}

Menghtiung volume balok C++ "program modify dua"

#include <iostream>
using namespace std;
class balok{
int p,l,t;
public:
void balook(int,int,int);
int hasil(void){
return(p*l*t)
;}
};
void balok::balook(int a,int b,int c){
p=a;
l=b;
t=c;
}

int main(){
balok blok, blk;
int s,n,l;
cout<<"Panjang: ";cin>>s;
cout<<"Lebar: ";cin>>n;
cout<<"Tinggi: ";cin>>l;
blok.balook(s,n,l);
blk.balook(4,3,2);
cout<<blok.hasil()<<endl;
cout<<blk.hasil();
}