C

create array

const fill = new Array(5).fill(0)
console.log(fill) // [ 0,0,0,0,0]

let filledArray = new Array(10).fill({'hello':'goodbye'});

declare array in javascript

const products=["watch", "pc", "mouse", "keyboard"];

how to declare an array in javascript

var array = [item1, item2, .....];
/*

  item1 and item2 could be a string (which is 
  a letter written in double or single quotes like this "string" or 'string') or 
  a number (which is just a normal number on the keypad) or a boolean (which is 
  an experssion which either returns to true of false) and the ..... means that 
  the inputs can be infinite.
  
*/

define array

const fruits = [
    "Apple",
    "Orange",
    "Mango",
    "Banana",
    "Cherry"
];

WHAT IS ARRAY AND HOW TO DECLARE ARRAY ?

// Quas : WHAT IS ARRAY AND HOW TO DECLARE ARRAY ?

// array is a single variable that is used to store different many of elements.

declare Array :
First you have to write var.
then you have to write a meaningful name.
then you have to give an equal sign.
then you have to give a third bracket.
then you have to give a single quotation inter the third bracket. 
then you have to give a element inter the single quotation.
then you have to give a comma. 
then you have to give a semicolon out of the third bracket .

example :
var friendsName = ['habib', 'iqbal', 'shorif', 'asraful', 'rasel', 'arif', 'deader' ];

declare an array

program arrayProg

   real :: numbers(5) !one dimensional real array
   integer :: matrix(3,3), i , j !two dimensional integer array
   
   !assigning some values to the array numbers
   do i=1,5
      numbers(i) = i * 2.0
   end do
   
   !display the values
   do i = 1, 5
      Print *, numbers(i)
   end do
   
   !assigning some values to the array matrix
   do i=1,3
      do j = 1, 3
         matrix(i, j) = i+j
      end do
   end do
   
   !display the values
   do i=1,3
      do j = 1, 3
         write(*,*) matrix(i,j)
      end do
   end do
   
   !short hand assignment
   numbers = (/1.5, 3.2,4.5,0.9,7.2 /)
   
   !display the values
   do i = 1, 5
      write(*,*) numbers(i)
   end do
   
end program arrayProg