#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <ctime>
using namespace std;

int main()
{
   int num1,
   num2,
   choice,
   studentAnswer,
   correctAnswer;

  srand(time(0));
  do
  {
    cout << "n-----------------------------------n"
         << "           Math Tutorn"
         << "            M E N Un"
         << "-----------------------------------n";
    cout << "1. Addition problemn";
    cout << "2. Subtraction problemn";
    cout << "3. Multiplication problemn";
    cout << "4. Division problemn";
    cout << "5. Quit this programn";
    cout << "------------------------------n";
    cout << "Enter your choice (1-5): ";
    cin >> choice;
    while (choice < 1 || choice > 5)
    {
        cout << "The valid choices are 1, 2, 3, "
            << "4, and 5. Please choose: ";
        cin >> choice;
    }
    switch (choice)
    {
    case 1:
        num1 = 1 + rand() % 500;
        num2 = 1 + rand() % 500;
        correctAnswer = num1 + num2;
        cout << "nn";
        cout << "  " << setw(4) << num1 << endl;
        cout << " +" << setw(4) << num2 << endl;
        cout << "  " << "----" << endl;
        cout << "   ";
        break;
    case 2:
        num1 = 1 + rand() % 999;
        num2 = 1 + rand() % 999;
        while (num2 > num1)
            num2 = 1 + rand() % 999;
        correctAnswer = num1 - num2;
        cout << "nn";
        cout << "  " << setw(4) << num1 << endl;
        cout << " -" << setw(4) << num2 << endl;
        cout << "  " << "----" << endl;
        cout << "   ";
        break;
    case 3:
        num1 = 1 + rand() % 100;
        num2 = 1 + rand() % 9;
        correctAnswer = num1 * num2;
        cout << "nn";
        cout << "  " << setw(4) << num1 << endl;
        cout << " *" << setw(4) << num2 << endl;
        cout << "  " << "----" << endl;
        cout << "   ";
        break;
    case 4:
        num2 = 1 + rand() % 9;
        num1 = num2 * (rand() % 50 + 1);
        correctAnswer = num1 / num2;
        cout << "nn";
        cout << "  " << num1 << " / " << num2 << " = ";
        break;
    case 5:
        cout << "Thank you for using Math Tutor.nn";
        break;
    }
    if (choice >= 1 && choice <= 4)
    {
        cin >> studentAnswer;
        if (studentAnswer == correctAnswer)
            cout << "nnCongratulations! That's right.nn";
        else
            cout << "nnSorry, the correct answer is " << correctAnswer
            << ".nn";
    }
  } while (choice != 5);
  return 0;
}