what is the problem with this code below?

Question

//calculate volume and surface area of a cone using c++ function programe
#include<iostream>
#include<cmath>
using namespace std;
double vcone(float r,float h);
double scone(float r,float h);
int main(){
float r,h;
cout<<"enter the values of r,and h:"<<endl;
cin>>r>>h;
cout<<"volume of a cone is:"<<vcone<<endl;
cout<<"surface area of a cone is:"<<scone<<endl;
return 0;
}
double vcone(float r,float h){
    const float pi=3.142;
    float volume;
    volume=1/3.0*pi*pow(r,2)*h;
    return volume;
}
double scone(float r,float h){
    const float pi=3.142;
    float surfacacearea;
    surfacacearea=pi*r*(r+sqrt(pow(h,2)+pow(r,2)));
    return surfacacearea;
}

Answer 1

header file for math function is wrong. it is #include<math.h> not #include<cmath>

Comments

Ok, but it gives constant values of vcone and scone for different r and h

Answer 2

When you call the functions in main ie vcone and scone you should also pass the radius and height in the function call. 

cout<<"volume of a cone is:"<<vcone(r, h)<<endl;
cout<<"surface area of a cone is:"<<scone(r, h)<<endl;

like so!