How can I remove an array element at a specific index only using pop?

user_16581817 0
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I want to create a function in JavaScript that, given an array and an index, the value in that index is removed. For example: removeAt([1,2,3,4],2) should return [1,2,4]. The only array method I can use is pop().

I came up with this(wondering if there is a more efficient way to do it):

function removeAt(arr, index) {
  var j = 0;
  var arr2 = [];
  for (var i = 0; i < arr.length - j; i++) {
    if (i != index) {
      arr2[i] = arr[i + j];
    } else {
      arr2[i] = arr[i + 1];
      j++;
    }
  }
  return arr2
}

console.log(removeAt([1, 2, 3, 4, 5], 3))

function arrays javascript
3 Answers

You should only add to the result array in the if condition, not else. Use j as the index in the result, don't add or subtract it.

function removeAt(arr, index) {
  var j = 0;
  var arr2 = [];
  for (var i = 0; i < arr.length; i++) {
    if (i != index) {
      arr2[j] = arr[i];
      j++;
    }
  }
  return arr2
}

console.log(removeAt([1, 2, 3, 4, 5], 3))

user_14918950

If you are not allowed to use any Array function except pop(), you may save memory space by not creating an extra variable using it.

function removeAt(arr, index){ 
    if(index>arr.length-1 || index<0) return arr;
    for(let i=0; i<arr.length; i++) {
        if(i>=index) {
            arr[i] = arr[i+1];
        }
    }
    arr.pop();
    return arr;  
}
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