//3 person
var a = new Object();
a.name="";
a.surname="";
var b = new Object();
b.name="";
b.surname="";
var c = new Object();
c.name="";
c.surname="";
//different fileds
a.patronymic="";
a.collorHair='';
a.sex='';
b.collorSkin='';
b.gender='';
b.presenceOfChildren='';
c.collorEyes='';
c.nationality='';
c.footSize='';
//fileds check
for ( let boobSyzze in a ) {
  if( boobSyzze != "name" || boobSyzze !=  "surname" || boobSyzze !=  "patronymic" || boobSyzze !=  "collorHair" || boobSyzze !=  "sex" );
  alert(boobSyzze);
}
for ( let boobSyzze in b ) {
  if( boobSyzze !=  "name" || boobSyzze !=  "surname" || boobSyzze !=  "collorSkin" || boobSyzze !=  "gender" || boobSyzze !=  "presenceOfChildren" );
  alert(boobSyzze);
}
for ( let boobSyzze in c ) {
  if( boobSyzze !=  "name" || boobSyzze !=  "surname" || boobSyzze !=  "collorEyes" || boobSyzze !=  "nationality" || boobSyzze !=  "footSize" );
  alert(boobSyzze);
}
//array of persons
let persons =[{}, {}, {}];
for (let key of persons){
  key.name = 'Mary';
  key.surname = 'Jain';
  key.familyDoctor = 'dr.Dre';
}
//loop of persons
for (let key of persons) { console.log(key);}
//loop of name and surname;
for (let key in persons){ 
  console.log(persons[key].name);
  console.log(persons[key].surname);
}
// loop of loop of values;
persons.forEach(function(keyOfPersone){
  for (let key in keyOfPersone){
    console.log(keyOfPersone[key]);
  }
});
//full name
persons.forEach(function(fullN){
  let counter = 0;
  for (let key in fullN){
    if (key==='name')
    counter++;
  }
  if (counter >= 1) {
  fullN.fullname = "Mary Jain";
  }
})
//serialize
let serialize = JSON.stringify(persons);
console.log(serialize);
//deserialize
let deserialize = JSON.parse('{"name": "2pac", "surname": "shakur", "familyDoctor":"Orlando Anderson", "fullName":"Lesane Parish Crooks"}');
persons.push(deserialize);
//HTML
var str = '<table border="1">';
for (let i = 0; i < persons.length; i++){
  str += '<tr style="background-color:black; color:yellow;">';
  for (let key in persons[i]){
    str += `<td>${persons[i][key]}</td>`;
  }
  str += '</tr>';
}
str += '</table>';
document.write(str);
//th