Delete duplicates of in 2-dimensional arrays

We have an array:

arr = []

And we make it 2-dimensional

arr = [
  [1, 2, 3, 4],
  [2, 3, 4, 5],
  [4, 3, 5, 2],
  [2, 3, 4, 5],
  [1, 2, 3, 4]
]

Now a question: How to delete duplicated 'lines' from an array?

• Line is second-dimensional array, lets say arr[0]: its contains 'line' => [1, 2, 3, 4], and arr[4] contains [1, 2, 3, 4].

So in result I need to get:

arr = [
  [1, 2, 3, 4],
  [2, 3, 4, 5],
  [4, 3, 5, 2],
]

We can do something like: get arr[0] and check it with arr[1], arr[2], arr[3]...

And then arr[1] with arr[2], arr[3]...

And so on...

But its too slow, so lazy...

Maybe there are some other methods?

I'll try arr.contains(arr[0]) with arr.removeElement(arr[0]), but some elements get lost :(

Try to create new array arr2 and put in it 'lines' from arr and then deleting them from arr:

arr2 = []
d = []
while arr.length > 0
  d = arr[0]
  arr2.push(d)
  arr.removeElement(d)
end

//arr2 missed some elements

Any suggestions?

1. sort the array.
2. rewrite (add) a new element to the new array, provided that the new element is different from the last element in the new array.
3. repeat step 2 for all elements of the input array.

printList = function( list )  
  print( list )
end

isEqual = function( subListA, subListB )
  local test = []
  test.push(true)
  subListA.forEach( function( element, index )
      if element != subListB[index] then
        test[0] = false
//        break
      end
    end
  )
  return test[0]
end

removeDupicate = function( list )
  local newList = []
  if list.length>-1 then
    newList.push( list[0] )
    for loop = 1 to list.length - 1
      if isEqual(list[loop],newList[newList.length-1])==false then
        newList.push( list[ loop ])
      end
    end
  end
  return newList
end
init = function()
  l = [  
    [1, 1, 0, 0],
    [1, 2, 3, 4],
    [2, 3, 4, 5],
    [4, 3, 5, 2],
    [2, 3, 4, 5],
    [1, 2, 3, 4],
    [1, 1, 1, 1],
    [1, 0, 1, 1],
    [1, 1, 0, 0],
    [1, 1, 1, 1]]
  l.sortList()

  l.forEach( printList )
  local newList = removeDupicate( l )
  print('Removed duplicate item')
  newList.forEach( printList )
end

update = function()
end

draw = function()
end

maybe this feature will come in handy Array.prototype.includes()

Loginus, thanks :)

Yes its works, but in my new project sorting is forbidden (since i have some SI:DI pointers in tree maker sorting kills the right result, unsorting function required, but it make program more slowly)...

So right now I have another method of tree making (will share, but it is too thin-specialized maths), but anyway thanks ;)