Put:

put move the hole ice cream.

Patch:

patch moves only ice cream cubes.

Graphical view

source from @VikasRajput

Array benefit

• Easily Traverse

• Filter

• Delete

• Update

• Create new data

JS array is dynamic

• Don't need to Specify the array type in high-level languages like JS or Python. In the other language, you have to specify the array type. Exp: C, C++, Java.

• Array size can increase/decrease. but other language array sizes are fixed.

• Don't need to collect garbage value.

can store any kind of data. Exp:

Multidimensional array

this array has two things column and a row. To find the data we will have two for loops one for the column & another for the row.

if we want the hobby of fehim then the code will look like

person [3][3]="Gamer"

Find out the length & LastIndex

length =lastIndex +1
lastIndex=length -1

Array Literal

Totaly on use it is not the dynamic way Most of cases we will use this method.

const arr=[ 3, 4,5,6,98]
consol.log(arr.length)
consol.log(arr)

Contractor pattern

js have two away to build object 1/Contractor pattern. 2/ factory pattern.
sometimes we have to give array length first in that cases we have to use a constructor pattern

const a1= new Array(5,33,5,6,7)  //in this case we are giving array length (5) first
console.log(a1.length)

Factory pattern

The main difference with the Constructor pattern is New But the prototype are same

const a1= Array(5)  //in this case we are giving array length (5,33,5,6,7) and New is not here
console.log(a1.length)

Array traversing

The benefit of traversing is to do a sum, average, greater number, and smaller number find out.

const arr = [2, 34, 346, 54, 131, 65, 435, 24, 345, 5, 23, 35, 33, 43]
let Largest = 0
let Smallest = 0
let secondLargest = 0
let secondSmallest = 0

let sum=0
for (let i=0;i<arr.length;i++){
    sum+=sum[i]
}
console.log(sum)            //find out sum number
console.log(sum/arr.length)  //find out averagr number
let largestNumber=arr[0]       //find out largest number
for (let i=1;i<arr.length;i++){
    if(arr[i]>largestNumber){
    largestNumber=arr[i]}
}
console.log(largestNumber)


for (let i = 0; i < arr.length; i++) {
    if (arr[i] > Largest) {            //find out secondLargest number
        secondLargest = Largest
        Largest = arr[i]
    } else if (arr[i] > secondLargest && Largest != secondLargest) {
        secondLargest = arr[i]
    }
}
console.log("secondLargest :", secondLargest)



let smallestNumber = arr[0] //find out smallest number
for (let i = 1; i < arr.length; i++) {
    if (arr[i] < smallestNumber) {
        smallestNumber = arr[i]
    }

}
console.log("Smallest :", smallestNumber)


for (let i = 0; i < arr.length; i++) {
    if (arr[i] > Smallest) {        //find out secondSmallest number
        secondSmallest = Smallest
        Smallest = arr[i]
    } else if (arr[i] < secondSmallest && Smallest != secondSmallest) {
        secondSmallest = arr[i]
    }
}
console.log("secondSmallest :", secondSmallest)

Array update

Array fill manual away

const arr1 = new Array(10);
for (let i = 0; i < arr1.length; i++) {
    arr1[i] = false
}
console.log(arr1)

Array fill method

const arr2 = new Array(10);
arr2.fill(0);
console.log(arr2)

Specifically array fill

const names = ["shihab", "fehim", "onto"]
names[0] = "shihab kabir"
names[1] = "fehim kabir"
names[3] = "onto kobir"
console.log(names)

Array fill & update

const response = new Array(9)
response.fill(false)
for (let i = 0; i < response.length; i++) {
    const rand = Math.floor(Math.random() * 10 + 1);
    response[i] = rand > 5 ? "X" : "O"
}
console.log(response)

Everything in Array

Array of Object

const faveChanal=[        //here we have a object
{name:"Stack learner" ,url:"https://www.youtube.com/playlist?list=PL_XxuZqN0xVD0op-QDEgyXFA4fRPChvkl"}

{name:"Traversy media" ,url:"https://www.youtube.com/@TraversyMedia/playlists"}

{name:"wes Bos" ,url:"https://www.youtube.com/results?search_query=wes+bos"}

{name:"freeCodeCamp" ,url:"https://www.youtube.com/results?search_query=freecodecamp"}
]

Array of functions

const sum = (a, b) => a + b; //here we have functions
const sub = (a, b) => a - b;
const multi = (a, b) => a * b;
const div = (a, b) => a / b;
const mod = (a, b) => a % b;
const funcs = [sum, sub, multi, div, mod] //here all function in array
const a = 10,
    b = 20;
for (let i = 0; i < funcs.length; i++) {
    const result = funcs[i](a, b)
    console.log(`[${funcs[i].name}] Result= ${result}`)
}

multi-dimensional Array

in multi-dimension, we need two loops or nested loops.

const twoDimArray = [
    [1, 2, 3],
    [4, 6],
    [7, 8, 9, 20]
];

for (let i = 0; i < twoDimArray.length; i++) {
    for (let j = 0; j < twoDimArray[i].length; j++) {  //here twoDimArray[i]=([i]) mean numberIndex & .length mean= sub-array length
        console.log(`Element at index [${i}][${j}] is ${twoDimArray[i][j]}`);
    }
}

Add in Array

Unshift is used to add data in the 0 indexes.

const arr1 = [1, 2, 3];
const arr2 = [8, 9];
arr1[arr1.length] = 4;
//this is genaral method
arr1.push(5);
arr1.push(8, 9)
console.log(arr1)
//this is push method
arr1.push(...arr2)
//this is new method for combind two array
Array.prototype.push.apply(arr1, arr2)
console.log(arr1)
//this is old method to combind to array

const arr3 = [6, 7, 8]
const arr4 = [11, 4, 12]

arr3.unshift(4)
console.log(arr3)
    //insert at beginning new method {here are (...)=that means splide method in ,splide method add two arr with out chidArray concept exmp: add arr3 & arr4 without (...) method look like [6,7,8,[11,4,12]] with (...) method [6,7,8,11,4,12] =here we can see no childArray
}
arr3.unshift(...arr4)
console.log(arr3)
//insert hole array in begining new method
Array.prototype.unshift.apply(arr3, arr4)
console.log(arr3)
//insert hole array in begining old method
const arr5 = [1, 2, 3, 4, 5]
arr5.splice(3, 0, 4) //splice(start: indexNumber, delete: indexNumber, ...additems: indexNumber)
console.log(arr5)

Update Existing element

const arr1=[2,3,4,5,6,7]
arr1[4]=1000
console.log(arr1)
//this is old method or scripting method
const Student=[
    {id:1,name:"Shihab"}
    {id:2,name:"Subbir"}
    {id:3,name:"Fehim"}
    {id:4,name:"Onto"}

]
const givinId=3;
const UpdateName=kabir
for(let i=0;i<stydent.legth;i++){
    if(givenId==Student[i].id){
    Student[i]=UpdateName
    break
}
}

Delete Item From An Array

const number =[1,2,3,4,5,6,7,8,9,10,11,12]
number.shift();
//it remove first element & you can add first element.
number.pop();
number.length=number.length-1
//it remove last element
number.splice(0,0,0)
//you can update,delete data by index number .splice(start: indexNumber, deletes: indexNumber, ...additems: indexNumber) ,you can delete multipul data by serice
const toBeDelete=5;
for(let i=0; i<number.length;i++){
     if(numbers[i]==toBeDeleted)}{
    number.splice(i,1)
}
}
//remove inside element -splice using value
const toBeDelete=6;
number= number.filter(item=> item!= toBeDelete)
//delete array by filter mathod


let xx=[2,4,5]
let yy=xx
xx.length=0
console.log(xx,yy)
//old method to rest data
while(number.length)number.pop()
console.log(number)

Array slice

It is an inclusive and exclusive method. Exp:

const =[1,2,3,4,5,6,7]
const sliced=arr.slice(0,5)
console.log(sliced)
//here first parameter inlusive(0+1)= index+1,last paramete Exclusive(5-1)=index-1
const cloned=arr.slice()
consol.log(arr==cloned)
false
 //here we can see the cloned address has been change & clone is not equile to arr.
function toArray(){
return Srray.prototype.slice.call(argument)
}
const argument=toArray(4,2,2,9,"test")
console.log(argument)
//array like Object : those who are acting like object but there not.

Stack

it is a data structure theory that explains data in & out of the process.
it works LIFO method =last in, first out
Exp

push & pop method

push & pop methods are used to add and delete data from the last index of the array. The POP & PUSH method comes from Stack DS

const text= hello
const JsStack=[]
for(let i=0;i<test.length;i++)
    JsStack.push(test.charAt(i)) // charAt is a method to call string
}
let result=""
while(JsStack.length) result= JsStack.pop()

Queue

Queue theory maintains FIFO= first in first out. Rare will increase (++) and the front is fixed= 0, push method= Enqueue & Pop is Dequeueff

Put & Patch

Put:

put move the hole ice cream.

Patch:

patch moves only ice cream cubes.

Graphical view

source from @VikasRajput

To Be Continue.....