#include <iostream>
using namespace std;

main()
{
    double var1, var2;

    beginning: // it kind of check point
    system("cls"); // clear terminal
    cout << "Enter first number: " << endl;
    cin >> var1;

    cout << "Enter second number: " << endl;
    cin >> var2;

    cout << "What do you want to do with that numbers?" << endl;
    cout << "+ - add" << endl;
    cout << "- - substract" << endl;
    cout << "* - multiply" << endl;
    cout << "/ - divide" << endl;

    char decision;

    cin >> decision;

    system("cls"); // clear terminal

    switch(decision)
    {
        case '+':
            cout << var1 << " + " << var2 << " = " << (var1 + var2) << endl;
            break;
        case '-':
            cout << var1 << " - " << var2 << " = " << (var1 - var2) << endl;
            break;
        case '*':
            cout << var1 << " * " << var2 << " = " << (var1 * var2) << endl;
            break;
        case '/':
            if (var2) //var2 != 0
                cout << var1 << " / " << var2 << " = " << (var1 / var2) << endl;
            else
                cout << "You can't divide by 0" << endl;
            break;
        default:
            cout << "You typed wrong character";

    }

    char decision2;

    cout << "Do you want to continue that program? (Y/N)" << endl;
    cin >> decision2;

    if (decision2 == 'y' || decision2 == 'Y')
        goto beginning;


}

#include <iostream>

using namespace std;

main()
{
    int a = 10;
    int b = 20;
    // CONDITION "?" so instruction that will be executed if condition is true : if condition is not true;
    string message = (a > b) ? "a > b" : "a <= b";

    cout << ((a > b ? a : b) + 10)<< endl; // if a>b is true it took a value, but is not true take b value

}

#include <iostream>

using namespace std;

main() {

    int minValue, maxValue, elementToCheck;
    bool isGreaterThanMinValue, isLowerThanMaxValue;

    cout << "Please input the minimum value: ";
    cin >> minValue;
    cout << "Please input the maximum value: ";
    cin >> maxValue;
    cout << "Please input the number to check: ";
    cin >> elementToCheck;

    isGreaterThanMinValue = (minValue <= elementToCheck);
    isLowerThanMaxValue = (elementToCheck <= maxValue);

    cout << "Is the value " << elementToCheck << " greater or equal to " << minValue << " ? " << isGreaterThanMinValue << endl;
    cout << "Is the value " << elementToCheck << " lower or equal to " << maxValue << " ? " << isLowerThanMaxValue << endl;



}

#include <iostream>
using namespace std;

main()
{
    char x = 'a';
    /*
        4.13412341234123412348888888
        4.13412341234123412345555555
    */
    switch (x)
    {
        case 'd':
            cout << "this is a place for the instructions that will be executed when switched value is equal to 0" << endl;
            break;
        case 25:
            cout << "this is a place for the instructions that will be executed when switched value is equal to 25" << endl;
            break;
        case 50:
            cout << "this is a place for the instructions that will be executed when switched value is equal to 50" << endl;
            break;
        default: // this one kind of "else" in python
            cout << "this is a place for the instructions that will be executed when value of switched variable is not equal to any case" << endl;
    }
}

#include <iostream>

using namespace std;

main ()
{
    int age;
    cout << "Please input your age: ";
    cin >> age;

    string isAdult = (age >= 18)
        ? "You are an adult please enter !"
        : "You are not an adult !";
// ? is the condition if true a in "?a:b" if not b in "?a:b"
    cout << isAdult;

}

#include <iostream>

using namespace std;

main ()
{
    int numberOfPoints;

    cout << "Enter the number of points you have achieved: ";
    cin >> numberOfPoints;

    if ((numberOfPoints >= 0) && (numberOfPoints <= 100))
    {
        string outputMessage = (numberOfPoints > 50)
            ? "You have passed the exam. Congratulations."
            : "You didn't pass the exam.";

        cout << outputMessage;
    }
    else
        cout << "ERROR. The number of points is invalid !";



}

#include <iostream>

using namespace std;

main ()
{
    int choice;

    cout << "1. January" << endl;
    cout << "2. February" << endl;
    cout << "3. March" << endl;
    cout << "4. April" << endl;
    cout << "5. May" << endl;
    cout << "6. June" << endl;
    cout << "7. July" << endl;
    cout << "8. August" << endl;
    cout << "9. September" << endl;
    cout << "10. October" << endl;
    cout << "11. November" << endl;
    cout << "12. December" << endl;
    cout << "Choose the month: ";

    cin >> choice;

    switch (choice)
    {
        case 1:
        case 3:
        case 5:
        case 7:
        case 8:
        case 10:
        case 12:
            cout << "This month has 31 days" << endl;
            break;
        case 4:
        case 6:
        case 9:
        case 11:
            cout << "This month has 30 days" << endl;
            break;
        case 2:
        {
            int year;
            cout << "Input the year: ";
            cin >> year;

            bool isLeapYear = (((year%4 == 0) && (year%100 != 0)) || (year%400 == 0));

            if (isLeapYear)
                cout << "The month february has 29 days in year " << year << endl;
            else
                cout << "The month february has 28 days in year " << year << endl;

        }
        default:
            cout << "ERROR. Invalid choice.";

    }



}