[C++] Square Circle Triangle

#include <iostream>
using namespace std;
void circle();
void triangle();
void square();

int main()
{
    int choice;
    cout << "Select the shape you would like to solve for: " << endl;
    cout << "1. Circle" << endl;
    cout << "2. Triangle" << endl;
    cout << "3. Square" << endl;
    cin >> choice;
    if (choice == 1)
    {
        circle();
    }
    else if(choice == 2)
    {
        triangle();
    }
    else if(choice == 3)
    {
        square();
    }
    return 0;
}
void circle()
{
    double area, circumference, radius;
    const double pi = 3.14;
    cout << "You have selected: Circle" << endl;
    cout << "Please enter the radius of the circle: " << endl;
    cin >> radius;
    area = pi * radius * radius;
    circumference = 2 * pi * radius;
    cout << "The Area of a Circle is: " << area << endl;
    cout << "The Circumference of a Circle is: " << circumference << endl;
}
void triangle()
{
    double area, height, base;
    cout << "You have selected: Triangle" << endl;
    cout << "Please enter the height of the triangle: " << endl;
    cin >> height;
    cout << "Please enter the base of the triangle: " << endl;
    cin >> base;
    area = .5 * base * height;
    cout << "The Area of the Triangle is: " << area << endl;
}
void square()
{
    double side, area, perimeter;
    cout << "You have selected: Square" << endl;
    cout << "Please enter the side of the square: " << endl;
    cin >> side;
    area = side * side;
    perimeter = 4 * side;
    cout << "The Area of the Square is: " << area << endl;
    cout << "The Preimeter of the Square is: " << perimeter << endl;
}