C# Online Compiler | .NET Fiddle

<no name> by Anonymous

/***************************************
*Name: Zachary Marcoux
*Date: 9/28/2023
Class Period : 4th
*Project Name: Math Quiz Application
*Project Description: Develop a Math Quiz Application that generates random math problems for users to solve. 
The application will utilize loops and arrays to repeatedly present questions and provide feedback to users.
***************************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Media;
using System.Text;
using System.Threading.Tasks;

namespace MathQuizApplication
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Random random = new Random();
            bool play = true; //declaring all variables to be used in the code
            int randomOpp = 0;
            int numProblems = 0;
            int answer = 0;
            string input = "";
            string difficulty = "";
            string[] allOperations = new string[] { "+", "*", "/", "-" };
            string[] medium = new string[] { "*", "/" };
            string[] easy = new string[] { "+", "-" };
            string operation = "";
            int correctAnswer = 0;
            int num1 = 0;
            int num2 = 0;
            double numCorrect = 0;
            int numIncorrect = 0;
            double percentCorrect = 0.0;
            do //while play is true (the user has not entered exit yet) the code will run
            {
                Console.WriteLine("Enter a mode to play: ");
                Console.WriteLine("\"Practice\"");
                Console.WriteLine("\"Game\"");
                Console.WriteLine("\"Exit\"");
                input = Console.ReadLine();
                input = input.ToLower(); //lowercases for easy comparing
                if (!input.Equals("exit") && !input.Equals("game") && !input.Equals("practice")) //checks if the user enters one of the options
                {
                    Console.WriteLine("Enter a valid input.");
                }
                if (input.Equals("exit"))
                {
                    play = false;
                }
                if (input.Equals("practice"))
                {
                    Console.WriteLine("Practice mode selected:");
                    Console.WriteLine("What type of questions would you like to practice?");
                    Console.WriteLine("Enter a plus sign (+) for addition: ");
                    Console.WriteLine("Enter an asterisk (*) for multiplication:");
                    Console.WriteLine("Enter a forward slash (/) for division");
                    Console.WriteLine("Enter a hyphen (-) for subtraction:");
                    operation = Console.ReadLine();
                    if (operation.Equals("+"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Addition"); //If the user selects addition for practice mode
                        operation = "Addition";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(101);
                            num2 = random.Next(101);
                            Console.WriteLine($"{num1} + {num2}");
                            correctAnswer = num1 + num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }

                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("*"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Multiplication"); //If the user selects multiplication for practice mode
                        operation = "Multiplication";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(13);
                            num2 = random.Next(13);
                            Console.WriteLine($"{num1} * {num2}");
                            correctAnswer = num1 * num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }

                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("/"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Division"); //If the user selects division for practice mode
                        operation = "Division";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(0, 13);
                            num2 = random.Next(0, 13) * num1;
                            while (num1 == 0)
                            {
                                num1 = random.Next(0, 13);
                            }
                            correctAnswer = num2 / num1;
                            Console.WriteLine($"{num2} / {num1}");
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }

                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("-"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Subtraction"); //If the user selects subtraction for practice mode
                        operation = "Subtraction";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(101);
                            num2 = random.Next(101);
                            Console.WriteLine($"{num1} - {num2}");
                            correctAnswer = num1 - num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }

                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }


                }
                if (input.Equals("game"))
                {
                    Console.WriteLine("Select a difficulty:");
                    Console.WriteLine("Easy  - Addition & Subtraction");
                    Console.WriteLine("Medium - Multiplication & Division");
                    Console.WriteLine("Hard  - All Operations");
                    difficulty = Console.ReadLine();
                    difficulty = difficulty.ToLower(); //lowercases for easy comparing
                    if (difficulty.Equals("easy"))
                    {
                        numProblems = 10;
                        Console.WriteLine("Addition and Subtraction Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 3);
                            operation = easy[randomOpp - 1];
                            if (operation.Equals("+"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} + {num2}");
                                correctAnswer = num1 + num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("-"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} - {num2}");
                                correctAnswer = num1 - num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    if (difficulty.Equals("medium"))
                    {
                        numProblems = 10;
                        Console.WriteLine("Multiplication and Division Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 3);
                            operation = medium[randomOpp - 1];
                            if (operation.Equals("*"))
                            {
                                num1 = random.Next(13);
                                num2 = random.Next(13);
                                Console.WriteLine($"{num1} * {num2}");
                                correctAnswer = num1 * num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("/"))
                            {
                                num1 = random.Next(0, 13);
                                num2 = random.Next(0, 13) * num1;
                                while (num1 == 0)
                                {
                                    num1 = random.Next(0, 13);
                                }
                                correctAnswer = num2 / num1;
                                Console.WriteLine($"{num2} / {num1}");
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    if (difficulty.Equals("hard"))
                    {
                        Console.WriteLine("All Operations Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 5);
                            operation = allOperations[randomOpp - 1];
                            if (operation.Equals("+"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} + {num2}");
                                correctAnswer = num1 + num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("-"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} - {num2}");
                                correctAnswer = num1 - num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("/"))
                            {
                                num1 = random.Next(0, 13);
                                num2 = random.Next(0, 13) * num1;
                                while (num1 == 0)
                                {
                                    num1 = random.Next(0, 13);
                                }
                                correctAnswer = num2 / num1;
                                Console.WriteLine($"{num2} / {num1}");
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("*"))
                            {
                                num1 = random.Next(13);
                                num2 = random.Next(13);
                                Console.WriteLine($"{num1} * {num2}");
                                correctAnswer = num1 * num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");


                    }
                }
            } while (play);
        }
    }
}

​x
 
/***************************************
*Name: Zachary Marcoux
*Date: 9/28/2023
Class Period : 4th
*Project Name: Math Quiz Application
*Project Description: Develop a Math Quiz Application that generates random math problems for users to solve. 
The application will utilize loops and arrays to repeatedly present questions and provide feedback to users.
***************************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Media;
using System.Text;
using System.Threading.Tasks;
​
namespace MathQuizApplication
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Random random = new Random();
            bool play = true; //declaring all variables to be used in the code
            int randomOpp = 0;
            int numProblems = 0;
            int answer = 0;
            string input = "";
            string difficulty = "";
            string[] allOperations = new string[] { "+", "*", "/", "-" };
            string[] medium = new string[] { "*", "/" };
            string[] easy = new string[] { "+", "-" };
            string operation = "";
            int correctAnswer = 0;
            int num1 = 0;
            int num2 = 0;
            double numCorrect = 0;
            int numIncorrect = 0;
            double percentCorrect = 0.0;
            do //while play is true (the user has not entered exit yet) the code will run
            {
                Console.WriteLine("Enter a mode to play: ");
                Console.WriteLine("\"Practice\"");
                Console.WriteLine("\"Game\"");
                Console.WriteLine("\"Exit\"");
                input = Console.ReadLine();
                input = input.ToLower(); //lowercases for easy comparing
                if (!input.Equals("exit") && !input.Equals("game") && !input.Equals("practice")) //checks if the user enters one of the options
                {
                    Console.WriteLine("Enter a valid input.");
                }
                if (input.Equals("exit"))
                {
                    play = false;
                }
                if (input.Equals("practice"))
                {
                    Console.WriteLine("Practice mode selected:");
                    Console.WriteLine("What type of questions would you like to practice?");
                    Console.WriteLine("Enter a plus sign (+) for addition: ");
                    Console.WriteLine("Enter an asterisk (*) for multiplication:");
                    Console.WriteLine("Enter a forward slash (/) for division");
                    Console.WriteLine("Enter a hyphen (-) for subtraction:");
                    operation = Console.ReadLine();
                    if (operation.Equals("+"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Addition"); //If the user selects addition for practice mode
                        operation = "Addition";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(101);
                            num2 = random.Next(101);
                            Console.WriteLine($"{num1} + {num2}");
                            correctAnswer = num1 + num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }
​
                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("*"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Multiplication"); //If the user selects multiplication for practice mode
                        operation = "Multiplication";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(13);
                            num2 = random.Next(13);
                            Console.WriteLine($"{num1} * {num2}");
                            correctAnswer = num1 * num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }
​
                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("/"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Division"); //If the user selects division for practice mode
                        operation = "Division";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(0, 13);
                            num2 = random.Next(0, 13) * num1;
                            while (num1 == 0)
                            {
                                num1 = random.Next(0, 13);
                            }
                            correctAnswer = num2 / num1;
                            Console.WriteLine($"{num2} / {num1}");
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }
​
                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    else if (operation.Equals("-"))
                    {
                        numCorrect = 0;
                        numIncorrect = 0;
                        Console.WriteLine("You chose Subtraction"); //If the user selects subtraction for practice mode
                        operation = "Subtraction";
                        Console.WriteLine("How many problems would you like to do?");
                        numProblems = int.Parse(Console.ReadLine());
                        for (int i = 0; i < numProblems; i++)
                        {
                            num1 = random.Next(101);
                            num2 = random.Next(101);
                            Console.WriteLine($"{num1} - {num2}");
                            correctAnswer = num1 - num2;
                            answer = int.Parse(Console.ReadLine());
                            if (correctAnswer == answer)
                            {
                                Console.WriteLine("That is correct.");
                                numCorrect++;
                            }
                            else if (correctAnswer != answer)
                            {
                                Console.WriteLine("That is incorrect.");
                                numIncorrect++;
                            }
​
                        }
                        percentCorrect = (numCorrect / numProblems) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
​
​
                }
                if (input.Equals("game"))
                {
                    Console.WriteLine("Select a difficulty:");
                    Console.WriteLine("Easy  - Addition & Subtraction");
                    Console.WriteLine("Medium - Multiplication & Division");
                    Console.WriteLine("Hard  - All Operations");
                    difficulty = Console.ReadLine();
                    difficulty = difficulty.ToLower(); //lowercases for easy comparing
                    if (difficulty.Equals("easy"))
                    {
                        numProblems = 10;
                        Console.WriteLine("Addition and Subtraction Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 3);
                            operation = easy[randomOpp - 1];
                            if (operation.Equals("+"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} + {num2}");
                                correctAnswer = num1 + num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("-"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} - {num2}");
                                correctAnswer = num1 - num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    if (difficulty.Equals("medium"))
                    {
                        numProblems = 10;
                        Console.WriteLine("Multiplication and Division Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 3);
                            operation = medium[randomOpp - 1];
                            if (operation.Equals("*"))
                            {
                                num1 = random.Next(13);
                                num2 = random.Next(13);
                                Console.WriteLine($"{num1} * {num2}");
                                correctAnswer = num1 * num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("/"))
                            {
                                num1 = random.Next(0, 13);
                                num2 = random.Next(0, 13) * num1;
                                while (num1 == 0)
                                {
                                    num1 = random.Next(0, 13);
                                }
                                correctAnswer = num2 / num1;
                                Console.WriteLine($"{num2} / {num1}");
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
                    }
                    if (difficulty.Equals("hard"))
                    {
                        Console.WriteLine("All Operations Selected.");
                        for (int i = 1; i <= 10; i++)
                        {
                            Console.WriteLine($"Question {i}:");
                            randomOpp = random.Next(1, 5);
                            operation = allOperations[randomOpp - 1];
                            if (operation.Equals("+"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} + {num2}");
                                correctAnswer = num1 + num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("-"))
                            {
                                num1 = random.Next(101);
                                num2 = random.Next(101);
                                Console.WriteLine($"{num1} - {num2}");
                                correctAnswer = num1 - num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("/"))
                            {
                                num1 = random.Next(0, 13);
                                num2 = random.Next(0, 13) * num1;
                                while (num1 == 0)
                                {
                                    num1 = random.Next(0, 13);
                                }
                                correctAnswer = num2 / num1;
                                Console.WriteLine($"{num2} / {num1}");
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                            else if (operation.Equals("*"))
                            {
                                num1 = random.Next(13);
                                num2 = random.Next(13);
                                Console.WriteLine($"{num1} * {num2}");
                                correctAnswer = num1 * num2;
                                answer = int.Parse(Console.ReadLine());
                                if (correctAnswer == answer)
                                {
                                    Console.WriteLine("That is correct.");
                                    numCorrect++;
                                }
                                else if (correctAnswer != answer)
                                {
                                    Console.WriteLine("That is incorrect.");
                                    numIncorrect++;
                                }
                            }
                        }
                        percentCorrect = (numCorrect / 10) * 100; //checks accuracy and displays percent correct
                        Console.WriteLine($"Number of Questions Answered: {numProblems}");
                        Console.WriteLine($"Number of problems correct: {(int)numCorrect}");
                        Console.WriteLine($"Number of problems incorrect: {numIncorrect}");
                        Console.WriteLine($"Percent correct: {percentCorrect}%");
​
​
                    }
                }
            } while (play);
        }
    }
}
​

View IL Code