0

JS - array: value becomes index ?

I do not understand the following case: a) x gets the value 2; but in arr[x] it becomes an index? Am I right with that? b) if i reuse x again, then it changes the value and not the index? I am confused. :-( Maybe someone out there can explain to me this, please.....? let x = 2; var arr = [4, 8, 16, 7, 41, 12]; console.log(arr); // output: [4, 8, 16, 7, 41, 12]; console.log(arr[x]); //output: 16 arr[x] = x + 1; console.log(arr[x]); // output: 3 arr[x] = x + 2; console.log(arr[x]); // output: 4 arr[x] = x + 3; console.log(arr[x]); // output: 5 console.log(arr); //output: [4, 8, 5, 7, 41, 12];

27th Jan 2022, 10:08 AM
Mylisa_beth
Mylisa_beth - avatar
2 odpowiedzi
+ 1
let x = 2; var arr = [4, 8, 16, 7, 41, 12]; // original array console.log(arr); // output: [4, 8, 16, 7, 41, 12]; // arr[x] means arr[2] (third element) => 16 console.log(arr[x]); //output: 16 // modify arr[2] (third element) // set its value to x + 1 (2 + 1) => 3 arr[x] = x + 1; console.log(arr[x]); // output: 3 // modify arr[2] (third element) // set its value to x + 2 (2 + 2) => 4 arr[x] = x + 2; console.log(arr[x]); // output: 4 // modify arr[2] (third element) // set its value to x + 3 (2 + 3) => 5 arr[x] = x + 3; console.log(arr[x]); // output: 5 // the modified array // this time the third element (index 2) // has value 5 // due to the latest modification above console.log(arr); //output: [4, 8, 5, 7, 41, 12];
27th Jan 2022, 10:34 AM
Ipang
+ 1
Thank you ! ! I was just irritated because x (as value) is outside the array. So I thought as it is a value. But that it is at the same time the index, I did not know.
27th Jan 2022, 12:37 PM
Mylisa_beth
Mylisa_beth - avatar