/**
 * Returns a list containing the stars that are not visible to the astronomer.
 *
 * @param stars a list of all stars in the universe
 * @param visible a list of stars that are visible to the astronomer
 * @return a list of stars that are not visible to the astronomer
 *
 * Exercise:
 * The astronomer wants to find the stars that are not visible to them.
 * Complete the code using an "else" statement and list operations to retrieve the desired result.
 */
fun findNotVisibleStars(stars: List<String>, visible: List<String>): List<String> {

    val notVisibleStars = mutableListOf<String>()
    for (star in stars) {
        if (star !in visible) {
            // Complete the code below to add the star to the notVisibleStars list
            // using list operations and an else statement
            notVisibleStars.add(star)
        }
    }
    return notVisibleStars
}
/**
 * Returns a list containing the stars that are not visible to the astronomer.
 *
 * @param stars a list of all stars in the universe
 * @param visible a list of stars that are visible to the astronomer
 * @return a list of stars that are not visible to the astronomer
 *
 * Exercise:
 * The astronomer wants to find the stars that are not visible to them.
 * Complete the code using an "else" statement and list operations to retrieve the desired result.
 */
fun findNotVisibleStars(stars: List<String>, visible: List<String>): List<String> {
/**
 * Returns a list containing the stars that are not visible to the astronomer.
 *
 * @param stars a list of all stars in the universe
 * @param visible a list of stars that are visible to the astronomer
 * @return a list of stars that are not visible to the astronomer
 *
 * Exercise:
 * The astronomer wants to find the stars that are not visible to them.
 * Complete the code using an "else" statement and list operations to retrieve the desired result.
 */
fun findNotVisibleStars(stars: List<String>, visible: List<String>): List<String> {

    val notVisibleStars = mutableListOf<String>()
    for (star in stars) {
        if (star !in visible) {
            // Complete the code below to add the star to the notVisibleStars list
            // using list operations and an else statement
            notVisibleStars.add(star)
        }
    }
    return notVisibleStars
}