una funcion para carrusel de imagenes

void carrusel (int a, int b)
{
	for (a = 1; a <= b; a++)
	{
		imagen1 = load_bitmap ("imagen1.bmp", NULL);
		blit (imagen1, screen, 0, 0, 0, 0, SCREEN_W, SCREEN_H);
		rest (3000);
		clear_to_color (screen, 0x000000);
		imagen2 = load_bitmap ("imagen2.bmp", NULL);
		blit (imagen2, screen, 0, 0, 0, 0, SCREEN_W, SCREEN_H);
		rest (3000);
		clear_to_color (screen, 0x000000);
		imagen3 = load_bitmap ("imagen3.bmp", NULL);
		blit (imagen3, screen, 0, 0, 0, 0, SCREEN_W, SCREEN_H);
		rest (3000);
		clear_to_color