How do I find if a string from list was used and exclude it from further use.

Questions & Answers
1

I am making a quiz game in Unity 2d and it’s almost complete (excluding all the questions, but that’s not important). All my questions and answers are in a List, they are in “questions” List and “correctAnswer” List. The questions are randomized and i want to make it that if a question is picked by random at least once, then it won’t be used again, meaning it won’t be used by the randomizer.

Sorry if i used something incorrectly, i’m a beginner.
What is in questions is not important it’s in another language.
P.S. I am looking for how to make random range not to repeat.

 List<string> questions = new List<string>() { "Pasaules augstākais kalns?", "Kas ir Vācijas galvaspilsēta?", "Kur atrodas ASV?", "Geo jautājums 4", "jt", "Geo jautājums 5", "Cik ir 2+2?", "Cik ir 12+1?", "Cik ir 9+10?", "Kvadrātsakne no 49", "2+2=5?" };

    List<string> correctAnswer = new List<string>() { "3", "1", "2", "3", "1", "2", "2", "3", "1", "1" };

    public static string selectedAnswer;

    public Transform resultObj;

    public static string choiceSelected = "n";

    public static int randQuestion = -1;

    public int catMod = 0;

    public Transform auraObj;

    public float totalCorrect = 0;

    public float totalQuestions = 0;

    public Transform scoreObj;

    public float scorePer;

    public Transform nextButton;

    public Transform firstText;
    public Transform secondText;
    public Transform thirdText;

    public Transform firstChild;
    public Transform secondChild;
    public Transform thirdChild;



    void Start()
    {
        if (selectCat.catTopic == "Matemātika")
        {
            catMod = 5;
        }

        if (selectCat.catTopic == "Ģeogrāfija")
        {
            catMod = 0;
        }
    }

    void FixedUpdate()
    {

        //scoreObj.GetComponent<TextMesh>().text = "Score  :  " +totalCorrect;   nextButton.GetComponent<Transform>().position = new Vector3(28.8f, 8.62f, 0);


        if (totalQuestions > 0)
        {
            scorePer = (totalCorrect / totalQuestions) * 100;
        }


        scoreObj.GetComponent<TextMesh>().text = "Score  :  " + scorePer+ "%";
        if (randQuestion == -1)
        {
            randQuestion = Random.Range(0 + catMod, 5 + catMod);

            nextButton.GetComponent<Transform>().position = new Vector3(49.1f, 8.62f, 0);

            firstText.GetComponent<BoxCollider2D>().offset = new Vector2(-0.1f, 0.2f);
            secondText.GetComponent<BoxCollider2D>().offset = new Vector2(-0.1f, 0.2f);
            thirdText.GetComponent<BoxCollider2D>().offset = new Vector2(-0.1f, 0.2f);

            firstChild.GetComponent<BoxCollider2D>().offset = new Vector2(0.05347621f, -5.174473f);
            secondChild.GetComponent<BoxCollider2D>().offset = new Vector2(0.05347621f, -5.174473f);
            thirdChild.GetComponent<BoxCollider2D>().offset = new Vector2(0.05347621f, -5.174473f);




        }

        if (randQuestion > -1)
        {
            GetComponent<TextMesh>().text = questions[randQuestion];
            
        }

        //Debug.Log(questions[randQuestion]);

        if (choiceSelected == "y")
        {
            choiceSelected = "n";
            totalQuestions += 1;


            if (correctAnswer[randQuestion] == selectedAnswer)
            {
                resultObj.GetComponent<TextMesh>().text = "Pareizi! Ejiet pa labi lai turpinātu";
                totalCorrect += 1;
                nextButton.GetComponent<Transform>().position = new Vector3(28.8f, 8.62f, 0);
                firstText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);
                secondText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);
                thirdText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);

                firstChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);
                secondChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);
                thirdChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);

            }

            else
            {
                NextButton.resetAura = "n";
                resultObj.GetComponent<TextMesh>().text = "Nepareizi!";

                if (correctAnswer[randQuestion] == "1")
                {
                    auraObj.GetComponent<Transform> ().position = new Vector3(-3.4f, 24.2f, 0);
                }

                if (correctAnswer[randQuestion] == "2")
                {
                    auraObj.GetComponent<Transform>().position = new Vector3(9.9f, 24.2f, 0);
                }

                if (correctAnswer[randQuestion] == "3")
                {
                    auraObj.GetComponent<Transform>().position = new Vector3(22.9f, 24.2f, 0);
                }

                nextButton.GetComponent<Transform>().position = new Vector3(28.8f, 8.62f, 0);
                firstText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);
                secondText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);
                thirdText.GetComponent<BoxCollider2D>().offset = new Vector2(50f, 0.2f);

                firstChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);
                secondChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);
                thirdChild.GetComponent<BoxCollider2D>().offset = new Vector2(50f, -5.174473f);
            }
        }

       
    }
}
2

i’d suggest making a copy of the list, call it “unusedQuestions” or something,
and when you choose an item from it at random, remove that item from the list.