Find the volume of a sphere

//pgm to find the volume of a sphere
#include<iostream.h>
#include<conio.h>
void main()
{
    float r,V;
    clrscr();
    cout<<"enter the radius of the sphere";
    cin>>r;
    V=(1.33*3.14*r*r*r);
    cout<<"volume="<<V;
    getch();
}