Warnings about conversions

I keep getting warnings about variable conversions, but dunno how to fix them. Can someone have a look and possibly fix it for me (very easy code)?

Warnings:

Quote:

---

main.cpp(10) : warning C4244: '=' : conversion from 'double' to 'float', possible loss of data
main.cpp(19) : warning C4244: '=' : conversion from 'double' to 'float', possible loss of data
main.cpp(57) : warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data
main.cpp(59) : warning C4244: 'argument' : conversion from 'int' to 'float', possible loss of data

---

Code:

Code:

---

#include <iostream.h> // input output


#define PI 3.14159

// Function for calculating the area of a circle
float area (float r)
{
        float a;
        a = PI * r * r;

        return(a);
}

// Function for calculating the circumference of a circle
float circumference (float r)
{
        float a;
        a = 2 * PI * r;

        return(a);
}

// Program start
int main ()
{
        // Declare needed variables
        int type;
        float answer;
        int n = 0;
        int radius;

        //Keep looping until a valid choice has been made
        do {
                cout << "What would you like to calculate?\n";
                cout << "1. Circumference\n";
                cout << "2. Area\n";
                cout << "Enter your choice: ";
                cin >> type;

                // Check if a valid choice has been made
                if (type == 1 || type == 2) {
                        // A valid choice has been made, exit loop
                        break;
                } else {
                        // Invalid choice, display error
                        cout << "Invalid Choice! Please try again\n\n";
                }
        } while (n != 1);

        // Ask for radius
        cout << "Please enter a radius for the circle: ";
        cin >> radius;

        // Use the functions to calculate
        if (type == 1) {
                answer = circumference(radius);
        } else if (type == 2) {
                answer = area(radius);
        }

        //Display answer
        cout << "The answer is: " << answer;

        //Exit Program
        return 0;
}

---

Well, in main, you declare radius as an int when you are passing it to a function that wants a float. You can fix it by declaring radius as a float.

Also, PI I think will implicitly be treated as a double, unless you place an 'f' at the end to signify that its a float

Code:

---

#include <iostream.h> // input output


#define PI 3.14159f

// Function for calculating the area of a circle
float area (float r)
{
        float a;
        a = PI * r * r;

        return(a);
}

// Function for calculating the circumference of a circle
float circumference (float r)
{
        float a;
        a = 2 * PI * r;

        return(a);
}

// Program start
int main ()
{
        // Declare needed variables
        int type;
        float answer;
        int n = 0;
        float radius;

        //Keep looping until a valid choice has been made
        do {
                cout << "What would you like to calculate?\n";
                cout << "1. Circumference\n";
                cout << "2. Area\n";
                cout << "Enter your choice: ";
                cin >> type;

                // Check if a valid choice has been made
                if (type == 1 || type == 2) {
                        // A valid choice has been made, exit loop
                        break;
                } else {
                        // Invalid choice, display error
                        cout << "Invalid Choice! Please try again\n\n";
                }
        } while (n != 1);

        // Ask for radius
        cout << "Please enter a radius for the circle: ";
        cin >> radius;

        // Use the functions to calculate
        if (type == 1) {
                answer = circumference(radius);
        } else if (type == 2) {
                answer = area(radius);
        }

        //Display answer
        cout << "The answer is: " << answer;

        //Exit Program
        return 0;
}

---

Thanks! Worked perfectly:)

A few corrections to the code, the first line is especially important.

Code:

---

#include <iostream> // input output
using namespace std;

const float PI = 3.14159f;

// Function for calculating the area of a circle
// NOTE: you don't need to store the
// result, you can directly return it.
// And since this function is so small
// you can even inline it (for faster code)
inline float area (float r)
{
        return PI * r * r;
}

// Function for calculating the circumference of a circle
// NOTE: same here
inline float circumference (float r)
{
        return 2 * PI * r;
}

// Program start
int main ()
{
        // Declare needed variables
        int type;
        float answer;
        int n = 0;
        float radius;

        //Keep looping until a valid choice has been made
        do {
                cout << "What would you like to calculate?\n";
                cout << "1. Circumference\n";
                cout << "2. Area\n";
                cout << "Enter your choice: ";
                cin >> type;

                // Check if a valid choice has been made
                if (type == 1 || type == 2) {
                        // A valid choice has been made, exit loop
                        break;
                } else {
                        // Invalid choice, display error
                        cout << "Invalid Choice! Please try again\n\n";
                }
        } while (n != 1);

        // Ask for radius
        cout << "Please enter a radius for the circle: ";
        cin >> radius;

        // Use the functions to calculate
        if (type == 1) {
                answer = circumference(radius);
        } else if (type == 2) {
                answer = area(radius);
        }

        //Display answer
        cout << "The answer is: " << answer;

        //Exit Program
        return 0;
}

---

Thanks:D