#include <iostream>

int main() {
    std::cout << "Hello, world!\n";

    double pi { 3.1415 };
    std::cout << "pi is approximately " << pi << std::endl;

    std::cout << "Enter a character: ";
    char c { };
    std::cin >> c;

    std::cout << "You entered " << c << "\n";
    
    return 0;
}