def display_ville(villes, screen, bv, pygame):
    """
    Dessine les villes à l'écran.
    """
    color = 255, 0, 0
    color2 = 0, 255, 0
    for v in villes:
        pygame.draw.circle(screen, color, (int(v[0]), int(v[1])), 5)
    v = villes[bv]
    pygame.draw.circle(screen, color2, (int(v[0]), int(v[1])), 5)
