//   Allows Keyboard Input.
   import java.util.Scanner;
   //   Generates Random Number
   import java.util.Random;

   //   Class name is "program"
    public class program {
    public static void main(String[] args) {
    // Initial Question, Displays Problem Choices
    System.out.println("How Many Questions Would You Like?");
    // Accept Input For How Many Questions That The User Wants
    Scanner sc = new Scanner(System.in);
    Double num;
    num = sc.nextDouble();
    // Sets Up How Many Times The Program Needs To Run To Repeat For How Many
    // Questions.
    Double questions;
    // Start To Count How Many Problems That The User Got Right.
    Double right;
    // Sets Needed Doubles To 0
    right = 0.0;
    questions = 0.0;
    // Update Questions Asked
    Double questionsasked;
    questionsasked = questions;
    // Will Repeat However Many Times That The User wants for questions.
    while (questions < num) { // Compares Initial value of questions to num,is how many questions that the
                                // user wants.
        // Ask User What Type Of Problem
        System.out.println("What Kind Of Problem Would You Like?");
        // 1 for Addition, 2 for Subtraction, 3 For Multiplication, 4 for Division
        System.out.println("1 for "+", 2 for "-", 3 for "*", 4 for "/"");
        // Takes Input Values For Problem Type
        Scanner sd = new Scanner(System.in);
        Double input;
        input = sc.nextDouble();
        // Register What Problem They Would Like
        // Input is what type of problem user wants
               if (input == 1) {
            // Addition Problem, Passes Number Of Questions Right, and other necessary
            // things
            // Adds Value To Number Of Questions Asked, Used To Find Percentage Correct
            questions = questions + 1.0;
            // Calls Method
            add(right, questions, questionsasked);
              } else if (input == 2) {
            // Subtraction Problem, Passes Number Of Questions Right, and other necessary
            // things
            // Adds Value To Number Of Questions Asked, Used To Find Percentage Correct
            questions = questions + 1.0;
            // Calls Method
            subtract(right, questions, questionsasked);

        } else if (input == 3) {
            // Multiply Problem, Passes Number Of Questions Right, and other necessary
            // things
            // Adds Value To Number Of Questions Asked, Used To Find Percentage Correct
            questions = questions + 1.0;
            // Calls Method
            multiply(right, questions, questionsasked);

        } else if (input == 4) {
            // Division Problem, Passes Number Of Questions Right, and other necessary
            // things
            // Adds Value To Number Of Questions Asked, Used To Find Percentage Correct
            questions = questions + 1.0;
            // Calls Method
            divide(right, questions, questionsasked);

        } else {
            // If Answer to what type of problem they want is not 1-4 it will print this.
            System.out.println("Not A Valid Problem.");
        }
    }
    Double calcper;
    calcper = right / questions;
    Double calcperfinal;
    calcperfinal = calcper * 100;
    System.out.println("You Got " + calcperfinal + "% Correct");
    // Lets User Know That The Program Is Done Running!
    System.out.println("Program Is Done Running!"); // This Is The Very Last Thing That Happens.
}

// Addition Method
public static Double add(Double right, Double questions, Double questionsasked) {
    // Computer FeedBack
    System.out.println("OK, Let's Add!");
    // THIS IS THE RANDOM NUMBER GENERATOR
    Random rand = new Random(); // This Declares The Random Number
    Double rnumber = rand.nextInt((int) 100.0) + 0.0; // 100 Is The Max, 0 Is The Min.
    // THIS IS THE RANDOM NUMBER GENERATOR 2
    Random rand2 = new Random(); // This Declares The Random Number
    Double rnumber2 = rand2.nextInt((int) 100.0) + 0.0; // 100 Is The Max, 0 Is The Min.
    // This Will Ask The Question!
    System.out.println("What Is, " + rnumber + " + " + rnumber2 + "?"); // This Will Ask Question.
    // Takes Input Values For What User Thinks Answer Is.
    Scanner sc = new Scanner(System.in);
    Double add; // This Is The User Answer
    add = sc.nextDouble(); // This Sets Current Scanner To The User Answer
    // Tell User If It Is Right Or Wrong!
    int answer = (int) (rnumber + rnumber2); // Creates INT To Determine The Right Answer
    // Used If user Got Question Correct
    if (add == answer) { // Compares User Answer To The Correct Computer Answer
        System.out.println("Correct!"); // Prints Out Correct
        right = right + 1.0;
        return right;
        // Used If user Got Question Incorrect
    } else {
        System.out.println("No, the correct answer is " + answer); // Prints The Correct Answer.
        return right;
    }
}

// Subtraction Method
public static Double subtract(Double right, Double questions, Double questionsasked) {
    // Computer Feedback
    System.out.println("OK, Let's Subtract!");
    // THIS IS THE RANDOM NUMBER GENERATOR
    Random rand = new Random(); // This Declares The Random Number
    Double rnumber = (double) (rand.nextInt(100) + 0.0); // 100 Is The Max, 0 Is The Min.
    // THIS IS THE RANDOM NUMBER GENERATOR 2
    Random rand2 = new Random(); // This Declares The Random Number
    Double rnumber2 = (double) (rand2.nextInt(100) + 0.0); // 100 Is The Max, 0 Is The Min.
    // This Will Ask The Question!
    System.out.println("What Is, " + rnumber + " - " + rnumber2 + "?"); // This Will Ask Question.
    // Takes Input Values For What User Thinks Answer Is.
    Scanner sc = new Scanner(System.in);
    Double sub; // This Is The User Answer
    sub = sc.nextDouble(); // This Sets Current Scanner To The User Answer
    // Tell User If It Is Right Or Wrong!
    int answer = (int) (rnumber - rnumber2); // Creates INT To Determine The Right Answer
    // Used If User gets Question Correct
    if (sub == answer) { // Compares User Answer To The Correct Computer Answer
        System.out.println("Correct!"); // Prints Out Correct
        right = right + 1;
        return right;
        // Used If User Gets Question Incorrect
    } else {
        System.out.println("No, the correct answer is " + answer); // Prints The Correct Answer.
        if (questionsasked == 1.0 || questions == 1.0 && right == 0.0) {
            System.out.println("You Got %0 Right.");
        } else {
            return right;
        }
    }
    return questions; // Updates Value Of Questions Asked
}

// Multiplication Method
public static Double multiply(Double right, Double questions, Double questionsasked) {
    // Computer FeedBack
    System.out.println("OK, Let's Multiply!");
    // THIS IS THE RANDOM NUMBER GENERATOR
    Random rand = new Random(); // This Declares The Random Number
    Double rnumber = (double) (rand.nextInt(100) + 0); // 100 Is The Max, 0 Is The Min.
    // THIS IS THE RANDOM NUMBER GENERATOR 2
    Random rand2 = new Random(); // This Declares The Random Number
    Double rnumber2 = (double) (rand2.nextInt(100) + 0); // 100 Is The Max, 0 Is The Min.
    // This Will Ask The Question!
    System.out.println("What Is, " + rnumber + " * " + rnumber2 + "?"); // This Will Ask Question.
    // Takes Input Values For What User Thinks Answer Is.
    Scanner sc = new Scanner(System.in);
    Double mul; // This Is The User Answer
    mul = sc.nextDouble(); // This Sets Current Scanner To The User Answer
    // Tell User If It Is Right Or Wrong!
    int answer = (int) (rnumber * rnumber2); // Creates INT To Determine The Right Answer
    // Used If User Gets Question Correct
    if (mul == answer) { // Compares User Answer To The Correct Computer Answer
        System.out.println("Correct!"); // Prints Out Correct
        right = right + 1.0;
        // Used If User Gets Question Incorrect
    } else {
        System.out.println("No, the correct answer is " + answer); // Prints The Correct Answer.
        return right;
    }
    return questions; // Updates Value Of Questions Asked
     }

// Division Method
public static Double divide(Double right, Double questions, Double questionsasked) {
    // Computer FeedBack
    System.out.println("OK, Let's Divide!");
    // THIS IS THE RANDOM NUMBER GENERATOR
    Random rand = new Random(); // This Declares The Random Number
    Double rnumber = (double) (rand.nextInt(100) + 0.0); // 100 Is The Max, 0 Is The Min.
    // THIS IS THE RANDOM NUMBER GENERATOR 2
    Random rand2 = new Random(); // This Declares The Random Number
    Double rnumber2 = (double) rand2.nextInt(100) + 0.0; // 100 Is The Max, 0 Is The Min.
    // This Will Ask The Question!
    System.out.println("What Is, " + rnumber + " / " + rnumber2 + "?" + ", Round To The Nearest 100th Place."); // This
                                                                                                                // Will
                                                                                                                // Ask
                                                                                                                // Question.
    // Takes Input Values For What User Thinks Answer Is.
    Scanner sc = new Scanner(System.in);
    Double div; // This Is The User Answer
    div = sc.nextDouble(); // This Sets Current Scanner To The User Answer
    // Tell User If It Is Right Or Wrong!
    double answer = (rnumber / rnumber2); // Creates Double To Determine The Right Answer
    double answerrounded = Math.round(answer * 100.0) / 100.0; // Creates Answer To The Nearest 100th
    // Used If User Gets Question Correct
    if (div == answerrounded) { // Compares User Answer To The Correct Computer Answer
        System.out.println("Correct!"); // Prints Out Correct
        right = right + 1.0;
        return right;
        // used If User Gets Question Incorrect
    } else {
        System.out.println("No, the correct answer is " + answerrounded); // Prints The Correct Answer.
    }
    return questions; // Updates Value Of Questions Asked
     }
 }