#include <iostream>
#include <cmath> // For 'atan()' which is the inverse fuction of 'tan' in C++,
// and for 'M_PI' which is the real number 'pi'.
void radius(); // Calculate the radius.
void theeta(); // Calculate the angle associated to the couple (x,y) in degree.
void main() {
int x, y;
cout << "Enter the x coordinate: " << flush;
cin >> x;
cout << "enter the y coordinate: " << flush;
cin >> y;
radius();
theeta();
}
void radius() {
float r;
r = sqrt(x*x + y*y);
cout << "Radius = " << r << endl;
}
void theeta() {
float theta, angle;
theta = atan(y/x); // 'theta' is the angle associated to the couple (x, y) in radian.
angle = theta*(180/M_PI); // The conversion of 'theta' from radian to degree.
cout << "Theta = " << angle << endl;
}