Undefined symbol: sf::RenderTarget::clear(sf::Color const&)

Undefined symbol: sf::RenderWindow::RenderWindow(sf::VideoMode, sf::String const&, unsigned int, sf::ContextSettings const&)

Undefined symbol: sf::RenderWindow::~RenderWindow()

Undefined symbol: sf::Color::Color(unsigned char, unsigned char, unsigned char, unsigned char)

Undefined symbol: sf::String::String(char const*, std::__1::locale const&)

Undefined symbol: sf::Window::close()

Undefined symbol: sf::Window::display()

Undefined symbol: sf::Window::pollEvent(sf::Event&)

Undefined symbol: sf::VideoMode::VideoMode(unsigned int, unsigned int, unsigned int)

Undefined symbol: sf::Window::isOpen() const

my code

#include <SFML/Graphics.hpp>

int main( )

{

    sf::RenderWindow Window( sf::VideoMode(640, 480), "game");

    while ( Window.isOpen()){

        sf::Event event;

        while (Window.pollEvent(event))

        {

            switch (event.type) {

                case sf::Event::Closed:

                    Window.close();

                    break;

            }

        }

        Window.clear();

        Window.display();

    }

}