#include
using namespace std;
class rectangle{
    private:
        int length,width;
    public:
        rectangle(int x,int y){
            length=x;
            width=y;
        }
        void set(int x,int y){
            length=x;
            width=y;
        }
        int area(){
            return length*width;
        }
};
class cuboid:public rectangle{
    private:
        int height;
    public:
        // write your code here...
        cuboid(int x,int y, int z) : rectangle(x,y){
            height = z;
        }
        int getvolume(){
            return area() * height;
        }
};
int main(){
    int x,y,z;
    cin>>x>>y>>z;
    cuboid a(x,y,z);
    cout<<a.getvolume();
    return 0;
}