// 3 persons
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
}

let b = {
    name: "Ivan",
    surname:"Bublik",
}

let c = {
    name: "Inna",
    surname: "Kulik",
}*/

// different fields
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 34,
    sex:"girl",
}

for (let k of [a,b,c]){
    console.log(k);
    if("age" in k){
        alert("age")
    }
}*/

//array of persons
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let person = [a, b, c];
person.push({name: "Igor", surname: "Kritov", age: 10, sex: "man"});
for (var k of person){
    console.log(k);
    if ("age" in k) {
      alert("age");
    }
}*/

//loop of persons
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a, b, c];
for(let i=0; i<persons.length; i++){
    console.log(persons[i])
}*/

//loop of name and surname

/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a, b, c];
for(let i=0; i<persons.length; i++){
    console.log(persons[i].name,persons[i].surname)
}*/

//loop of loop of values
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a, b, c];
for(let i=0; i<persons.length; i++){
    for(let value in persons[i]){
        console.log(persons[i][value])
    }
}*/

//fullName
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a, b, c];
for(let i=0; i<persons.length; i++){
        if ("name" in persons[i] && "surname" in persons[i] && "fathername" in persons[i]) {
            persons[i].fullName = persons[i].name +" " + persons[i].surname + " " + persons[i].fathername;
}else if("name" in persons[i] && "surname" in persons[i]){
    persons[i].fullName = persons[i].name +" " + persons[i].surname;
}
console.log(persons[i])
}*/

//serialize

/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}

let persons = [a, b, c];

let json = JSON.stringify(persons)
console.log(json) */

/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}

let persons = [a,b,c]
let json = JSON.stringify(persons)
let persons2 = JSON.parse(json)
persons.push(persons2[1])
console.log(persons)*/

//HTML
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a,b,c]
var str = "<table border='1'>"
str +=`<td>Name</td>`
str +=`<td>Surname</td>`
for (let i=0;i<persons.length;i++){
    str += `<tr><td>${persons[i].name}<td>${persons[i].surname}</td></td></tr>`
}
str += "</table>"

console.log(str)
document.write(str)*/

//HTML optional fields
/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 30,
    sex:"girl",
}
let persons = [a,b,c]
var str = "<table border='1'>"
str +=`<td>Name</td>`
str +=`<td>Surname</td>`
str +=`<td>Age</td>`
str +=`<td>Sex</td>`
for (let i=0;i<persons.length;i++){
    str += `<tr style="background-color:green"><td>${persons[i].name}<td>${persons[i].surname}</td><td>${persons[i].age}</td></td><td>${persons[i].sex}</td></td></tr>`
}
str += "</table>"

console.log(str)
document.write(str)*/

/*let a = {
    name: "Andrey",
    surname: "Ivanov",
    age: 20,
    sex:"man"
}

let b = {
    name: "Ivan",
    surname:"Bublik",
    age: 30,
    sex:"man",
    fathername:"Igorovich"
}

let c = {
    name: "Inna",
    surname: "Kulik",
    age: 43,
    sex:"girl",
}



arr = [a,b,c]
let Names = [];
let row = '<tr>';
str = '<table style="border: 2px double black;" border = "1" >';

for (let obj of arr) {
for (let key in obj) {
    if(!Names.includes(key)) {
        Names.push(key);
       row += '<th>' + key + '</th>';
    }
}
}
row += '</tr>'

for (let obj of arr){
row += '<tr>';
for (let key of Names){

    if (obj[key]){
        row += '<td>' + obj[key] + '</td>';
    } else {
        row += '<td></td>';
    }
}
row += '</tr>';
}

str += row + '</table>'
document.write(str)*/