URI - Problem 1012 - Area

#include<iostream>
#include<iomanip> //for setprecision()
#include<cmath> //for pow()

using namespace std;

int main()
{
    double pi = 3.14159, a, b, c;

    cin >> a;
    cin >> b;
    cin >> c;

    double area_of_triangle = 0.5 * a * c;
    double area_of_circle = pi * pow(c, 2);
    double area_of_trapezium = ((a+b) * c)/2;
    double area_of_square = pow(b, 2);
    double area_of_rectangle = a*b;

    cout << "TRIANGULO: " << fixed << setprecision(3) << area_of_triangle << endl;
    cout << "CIRCULO: " << fixed << setprecision(3) << area_of_circle << endl;
    cout << "TRAPEZIO: " << fixed << setprecision(3) << area_of_trapezium << endl;
    cout << "QUADRADO: " << fixed << setprecision(3) << area_of_square << endl;
    cout << "RETANGULO: " << fixed << setprecision(3) << area_of_rectangle << endl;

    return 0;
}