I did the exercise, almost all the outputs are coming out as the URI output is asking, however the first requirement is not as it asks in the program. I used the setprecision, but I'm not sure why the first result does not round 3 decimal places after the comma. to 3.0 b 4.0 c 5.2
TRIANGULO: 7.800 CIRCULO: 84.949 TRAPEZIO: 18.200 QUADRADO: 16.000 RETANGULO: 12.000
My first TRIANGLE output leaves only 7.8 and the others exit perfectly.
#include <iostream>
#include <iomanip>
#include <math.h>
int main(int argc, char** argv)
{
double pi = 3.14159;
double a, b, c;
double area_triangulo, area_circulo, area_trapezio,
area_quadrado,area_retangulo;
std::cin >> a >> b >> c;
area_triangulo = a * c / 2;
area_circulo = pi * pow(c, 2);
area_trapezio = ((a + b)* c)/2;
area_quadrado = pow(b, 2);
area_retangulo = a * b;
std::cout << "TRIANGULO: " <<area_triangulo << std::setprecision(5)<<
std::fixed << std::endl;
std::cout << "CIRCULO: " <<area_circulo << std::setprecision(3)<<
std::fixed << std::endl;
std::cout << "TRAPEZIO: " <<area_trapezio << std::setprecision(3)<<
std::fixed << std::endl;
std::cout << "QUADRADO: " <<area_quadrado << std::setprecision(3)<<
std::fixed << std::endl;
std::cout << "RETANGULO: " <<area_retangulo << std::setprecision(3)<<
std::fixed << std::endl;
return 0;
}