Exlude only the middle ID's of flags in a row

I have 2 arrays

IDList ["01","02","03","04"]

Which contains some ID’s of something.

And i have an another list of ID who tells which element of IDList possess the flag example

IDLISTPRD["01","02","03","04"]

As you see here all elements of IDList possess the flag according to IDLISTPRD

I want to check if any of this ID has 3 flags in a row.

I have made this code

  let eqObj = {};
       for (var i = 0; i < IDLISTPRD.length; i++) {
              if (IDList.includes(IDLISTPRD[i])) {
              eqObj[IDLISTPRD[i]] = IDList.indexOf(IDLISTPRD[i]);
                 }
       }

First i am pushing elements(ID’s) that are the same (possess the flag)

According to 2 arrays this will return eqObj [ ["01" : 0,"02" : 1,"03" : 2,"04" : 3]]

In order to compare them i will have to sort them

let objSorted = Object.entries(eqObj ).sort(function (a, b) {
                        return b[1] - a[1];
                    });

                    let flagInRow= 0;
                    let flagInRowIndicator= true;

                    for (var i = 0; i < objSorted .length - 1; i++) {
                        if (objSorted [i][1] - objSorted [i + 1][1] == 1) {
                            flagInRow++;
                        } else {
                            flagInRow= 0;
                        }

                        if (flagInRow< 2) {
                            flagInRowIndicator= true;
                        } else {
                            flagInRowIndicator= false;
                            break;
                        }
                    }

As you can see here the flaginRowIndicator turn true when it finds 3 flags in a row
now i am trying to keep the logic but to remove the middle element of the array
example
if i have the array with

["1","2","3"] 

where three of this have flags i want to remove the middle one and to return an array with only ["1,"3"]

Another example if it would have 6 flags in a row ["1","2","3","4","5","6"]
I want to remove only the middle ones of 3 rows like in this case to remove 2 and 5 and to return

["1","3","4","6"]

>Solution :

You could iterate from the end and splice the array.

function removeMiddle(array) {
    let i = array.length - 2;
    while (i > 0) {
        array.splice(i, 1);
        i -= 3;
    }
    return array;
}

console.log(removeMiddle([1, 2, 3]));
console.log(removeMiddle([1, 2, 3, 4, 5, 6]));