// Exercises: Level 1

//     Create an empty object called dog
//     Print the the dog object on the console
//     Add name, legs, color, age and bark properties for the dog object.The bark property is a method which return woof woof
//     Get name, legs, color, age and bark value from the dog object
//     Set new properties the dog object: breed, getDogInfo

// Exercises: Level 2

//     Find the person who has many skills in the users object.

//     Count logged in users, count users having greater than equal to 50 points from the following object.

// const users = {
//     Alex: {
//         email: 'alex@alex.com',
//         skills: ['HTML', 'CSS', 'JavaScript'],
//         age: 20,
//         isLoggedIn: false,
//         points: 30
//     },
//     Asab: {
//         email: 'asab@asab.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'Redux', 'MongoDB', 'Express', 'React', 'Node'],
//         age: 25,
//         isLoggedIn: false,
//         points: 50
//     },
//     Brook: {
//         email: 'daniel@daniel.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'React', 'Redux'],
//         age: 30,
//         isLoggedIn: true,
//         points: 50
//     },
//     Daniel: {
//         email: 'daniel@alex.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'Python'],
//         age: 20,
//         isLoggedIn: false,
//         points: 40
//     },
//     John: {
//         email: 'john@john.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'React', 'Redux', 'Node.js'],
//         age: 20,
//         isLoggedIn: true,
//         points: 50
//     },
//     Thomas: {
//         email: 'thomas@thomas.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'React'],
//         age: 20,
//         isLoggedIn: false,
//         points: 40
//     },
//     Paul: {
//         email: 'paul@paul.com',
//         skills: ['HTML', 'CSS', 'JavaScript', 'MongoDB', 'Express', 'React', 'Node'],
//         age: 20,
//         isLoggedIn: false,
//         points: 40
//     }
// }```

//     Find people who are MERN stack developer from the users object

//     Set your name in the users object without modifying the original users object

//     Get all keys or properties of users object

//     Get all the values of users object

//     Use the countries object to print a country name, capital, populations and languages.

// Exercises: Level 3

//     Create an object literal called personAccount. It has firstName, lastName, incomes, expenses properties and it has totalIncome, totalExpense, accountInfo,addIncome, addExpense and accountBalance methods. Incomes is a set of incomes and its description and expenses is a set of incomes and its description.
//     **** Questions:2, 3 and 4 are based on the following two arrays:users and products ()

//     const users = [
//     {
//         _id: 'ab12ex',
//         username: 'Alex',
//         email: 'alex@alex.com',
//         password: '123123',
//         createdAt:'08/01/2020 9:00 AM',
//         isLoggedIn: false
//     },
//     {
//         _id: 'fg12cy',
//         username: 'Asab',
//         email: 'asab@asab.com',
//         password: '123456',
//         createdAt:'08/01/2020 9:30 AM',
//         isLoggedIn: true
//     },
//     {
//         _id: 'zwf8md',
//         username: 'Brook',
//         email: 'brook@brook.com',
//         password: '123111',
//         createdAt:'08/01/2020 9:45 AM',
//         isLoggedIn: true
//     },
//     {
//         _id: 'eefamr',
//         username: 'Martha',
//         email: 'martha@martha.com',
//         password: '123222',
//         createdAt:'08/01/2020 9:50 AM',
//         isLoggedIn: false
//     },
//     {
//         _id: 'ghderc',
//         username: 'Thomas',
//         email: 'thomas@thomas.com',
//         password: '123333',
//         createdAt:'08/01/2020 10:00 AM',
//         isLoggedIn: false
//     }
//     ];

//     const products = [
//   {
//     _id: 'eedfcf',
//     name: 'mobile phone',
//     description: 'Huawei Honor',
//     price: 200,
//     ratings: [
//       { userId: 'fg12cy', rate: 5 },
//       { userId: 'zwf8md', rate: 4.5 }
//     ],
//     likes: []
//   },
//   {
//     _id: 'aegfal',
//     name: 'Laptop',
//     description: 'MacPro: System Darwin',
//     price: 2500,
//     ratings: [],
//     likes: ['fg12cy']
//   },
//   {
//     _id: 'hedfcg',
//     name: 'TV',
//     description: 'Smart TV:Procaster',
//     price: 400,
//     ratings: [{ userId: 'fg12cy', rate: 5 }],
//     likes: ['fg12cy']
//   }
// ]

// Imagine you are getting the above users collection from a MongoDB database. a. Create a function called signUp which allows user to add to the collection. If user exists, inform the user that he has already an account.
// b. Create a function called signIn which allows user to sign in to the application

//     The products array has three elements and each of them has six properties. a. Create a function called rateProduct which rates the product b. Create a function called averageRating which calculate the average rating of a product

//     Create a function called likeProduct. This function will helps to like to the product if it is not liked and remove like if it was liked.

// 🎉 CONGRATULATIONS ! 🎉