Advent of Code Day 5 Part 2

#NoEnv
SetBatchLines, -1
SetWorkingDir, %A_ScriptDir%

FileRead, read_file, Input.txt

seats := StrSplit(read_file, "`r`n")

SeatIds := []

For each, seat in seats
{
    row := 0
    For i, char in StrSplit(SubStr(seat, 1, 7))
    {
        row += (2**(7-i)) * (char == "F" ? 0 : 1)
    }
    column := 0
    For i, char in StrSplit(SubStr(seat, 8))
    {
        column += (2**(3-i)) * (char == "L" ? 0 : 1)
    }
    SeatIds[row * 8 + column] := 1
}

result := 0
Loop, % SeatIds.MaxIndex()
{
    If (A_Index > SeatIds.MinIndex())
    {
        If (SeatIds[A_Index] != 1)
        {
            result := A_Index
            Break
        }
    }

}

Clipboard := result
MsgBox, % result