# Need advice on how to fix

• 03-01-2006
Surfndog
Need advice on how to fix
Ok so i am building a beginners program, to have a user input the center of a circle and then a point and find the radius, diameter, area, and circumference. I am suppose to use predefined functions and value returning functions. I put the error of what the compiler said on the line it had a problem with using comments please help if you can.

Code:

```#include <iostream> #include <cmath> #include <iomanip> using namespace std; double radius(double x, double y, double w, double z); double diameter(double x); double circumference(double x); double area(double x); const double p = 3.1416; int main() {         double orgin1, orgin2, pt1, pt2, radius, diameter, circumference;                 cout << setprecision(2) << fixed << showpoint;                 cout << "Please input the origin of your circle" << endl;         cin >> orgin1 >> orgin2;         cout << "Please input a point on the circle" << endl;         cin >> pt1 >> pt2;         cout << "Your origin is: " << "(" << orgin1 << "," << orgin2 << ")" << endl;         cout << "Your point is: " << "(" << pt1 << "," << pt2 << ")" << endl;         cout << "The radius of your circle is: "                 << radius(pt1, orgin1, pt2, orgin2) << endl;// term doesn't evaluate 4arguements         cout << "The diameter of your circle is: " << diameter(radius) << endl;// term         cout << "The circumference of your circle is: "      // doesn't evaluate 1 arguement                 << circumference(diameter) << endl; // term doesn't evaluate 1 argument         cout << "The area of your circle is: " << area(radius) << endl;         return 0; } double radius(double x, double y, double w, double z) {         double radius, sum;         x = pow(x-y,2);         w = pow(w-z,2);     sum = x + w;         radius = sqrt(sum);         return radius; } double diameter(double x) {         double diameter;         diameter = 2 * x;         return diameter; } double circumference(double x) {         double cicumference;         circumference = p * x;         return circumference; // cannot convert from double to double } double area(double x) {         double area;         x = pow(radius, 2); // none of the 7 overloads can convert parameter 1 from         area = p * x;      // type double         return area; }```
• 03-01-2006
spydoor
The problem is your variables have the same names as your functions.
• 03-01-2006
Bench82
some of the variables are kind-of unnecessary too, although there'd be nothing wrong with them if they had different names

eg,
Code:

`double circumference(double d) { return pi*d; }`
Also, you may find that your implementation already has "pi" defined as a constant somewhere.