//html tree
let obj = {
    body: {
        tagName: 'body',
        attrs: {},
        paired: true,
        subTags: [
            {
                tagName: 'div',
                attrs: {},
                paired: true,
                subTags: [
                    {
                        tagName: 'span',
                        attrs: {},
                        paired: true,
                        text: 'Enter data please:',
                    },
        
                    {
                        tagName: 'br',
                        paired: false
                    },
        
                    {
                        tagName: 'input',
                        attrs: {
                            type: 'text',                            
                            id: 'name'
                        },
                        paired: false
                    },
        
                    {
                        tagName: 'input',
                        attrs: {
                            type: 'text',
                            id: 'surname'
                        },
                        paired: false
                    }
                ]
            },
            {
                tagName: 'div',
                attrs: {},
                paired: true,
                subTags: [
                    {
                        tagName: 'button',
                        attrs: {
                            id: 'ok'
                        },
                        paired: true,
                        text: 'Ok'
                        
                    },
                    {
                        tagName: 'button',
                        attrs: {
                            id: 'cancel'
                        },
                        paired: true,
                        text: 'Cancel'
                    },
                ],
            },
        ]
    }
}

console.log(`<button id='cancel'> innerText:`, obj.body.subTags[1].subTags[1].text)
console.log(`<input type='text' id='surname'> id:`, obj.body.subTags[0].subTags[3].attrs.id)

//declarative fields
var notebook = {
    brand: prompt('Notebook brand:','') || "HP",
    type:  prompt('Notebook type:','') || "440 G4",
    model: prompt('Notebook model:','') || "Y7Z75EA",
    ram: +prompt('Notebook ram:','') || 4,
    size: prompt('Notebook size:','') || "14",
    weight: +prompt('Notebook weight:','') ||1.8,
    resolution: {
        width: +prompt('Notebook width:','') || 1920,
        height: +prompt('Notebook height','') || 1080,
    },
};
console.log(notebook)

var phone = {
    brand: prompt('Phone brand:','') || "meizu",
    model: prompt('Phone model:','') || "m2",
    ram: +prompt('Phone amount of ram:','') || 2,
    color: prompt('Phone color','') || "black",
};
console.log(phone)


var person = {
    Name: prompt('Person name:','') || 'Donald',
    surname: prompt('Person surname:','') || "Trump",
    married: confirm('is married?'),
}
console.log(person)

//object links
notebook.owner = phone.owner = person
person.phone = phone
person.notebook = notebook
console.log(phone, notebook)
console.log(person.phone.owner.notebook.owner.phone == person.phone )

//imperative array fill 3
let imperatve = [prompt('input array[0] element','')||0, prompt('input array[1] element','')||1, prompt('input array[2] element','')||2]
console.log(imperatve)

//while confirm
while(!confirm('break the loop?')){}

//array fill
let arrayFill = []
for(let i = 0, str; i < arrayFill.length+1; i++) {
    str = prompt('input array element','')

    if(!str && str !== '') {
        break;
    } else {
        arrayFill.push(str)
    }
}
console.log(arrayFill)

let arrayNoPush = []
for(let i = 0, str2; i < arrayNoPush.length+1; i++) {
    str2 = prompt('input arrayNoPush element','')

    if(!str2 && str2 !== '') {
        break;
    } else {
        arrayNoPush[arrayNoPush.length] = str2
    }
}
console.log(arrayNoPush)

//infinite probability
let trys = 0
while(true) {
    trys++
    let rand = Math.random()
    if(rand > 0.9) {
        alert(`Number of iterations: ${trys}`)
        break;
    }
}

//empty loop
while(!prompt('Input smth and press OK to stop','')){}

//progression sum
let N = 10
let step = 1
let sum = 0
for(let i = 1; i <= N; i++) {
    sum = sum + step
    step += 3
}
console.log('progression sum:', sum)

//chess one line
let strlen = 11
let str = ''
for(let i = 0; i < strlen; i++) {
    i % 2 === 0? str += ' ' : str += '#'
}
console.log(str, str.length)

//numers
let numbers = ''
for(let i = 0; i < 10; i++) {
    for(let i = 0; i < 10; i++) {
        numbers += `${i}`
    }
    numbers += '\n'
}
console.log(numbers)