Problem about the Intermediate Algorithm Scripting: Drop it

Tell us what’s happening:

if (func(arr[0])) {

In that part why we need to use arr[0] rather than using arr[i]. if we use arr[i] it also stands for arr[0] but why can’t we use arr[i]??

Your code so far

function dropElements(arr, func) {
// drop them elements.
var times = arr.length;
for (var i = 0; i < times; i++) {
  if (func(arr[0])) {
  } else {
return arr;

console.log(dropElements([1, 2, 3, 4], function(n) {return n >= 3;}));

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Challenge: Drop it

Link to the challenge:

Hey @mr.chan1997,

It’s like that because if you used arr[i] it will change everytime the for loop changes the i variable. so it will loop through the 1st item, then delete it. Then it loops through the 2nd item after the first one is deleted here’s what it will visually look like.

let arr = [1, 2, 3, 4, 5]
// Loop 1 - i = 0. deletes the first element.
arr[i] -> arr[0] = 1;
console.log(arr) // [2, 3, 4, 5]
// Loop 2 - i = 1. Deletes the second elmnt after the 1st one is deleted
arr[i] -> arr[1] = 3;
console.log(arr) // [2, 4, 5]

Eventually, it goes on until it goes beyond the array size. By using a fixed amount of 0 which is always going to be at the beginning of an array.

Hope this helps understand! :slight_smile:

OH~~ thank you :heart_eyes: :heart_eyes: :heart_eyes: :heart_eyes:

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