Javascript:Guess Output of given code

 

Code:Guess Output of following code

Code:

const x=[];

x[4] = 1;

x.forEach((item,index,array)=>{

   console.log(`${item} at index = ${index}`);

})

Output:

1 at index = 4

Explaination:

in array x length is 5 but all element from index 0,1,2,3

are not initialized and are defined as empty,foreach loop

only over array element which are not empty hence forEach

will give console.log for only 4th index.