matrix 2.0

function create()
  new = {}
  return new
end

function set(array, x, y, value)
  index = x..":"..y
  array[index] = value
end

function get(array, x, y)
  index = x..":"..y
  return array[index]
end

function remove(array, x, y)
  index = x..":"..y
  array[index] = nil
end

function size(array)
  numItems = 0
  for k,v in pairs(array) do
    numItems = numItems + 1
  end
  return(numItems)
end