I've just started learning c++ and am trying to write a program for finding the area of a circle. I've written the program and whenever I try to compile it I get 2 error messages. The first is:

areaofcircle.cpp:9:14: error: expected unqualified-id before numeric constant

and the second is:

areaofcircle.cpp:18:5: error: 'area' was not declared in this scope

What should I do? I would post a picture, but I'm a new user, so I can't.

#include <iostream> 
using namespace std; 
#define pi 3.1415926535897932384626433832795 
int main() 
{
    // Create three float variable values: r, pi, area 
    float r, pi, area; 
    cout << "This program computes the area of a circle." << endl; 

    // Prompt user to enter the radius of the circle, read input value into variable r 
    cout << "Enter the radius of the circle " << endl; 
    cin >> r; 

    // Square r and then multiply by pi area = r * r * pi; 
    cout << "The area is " << area << "." << endl; 
}