function table.arrayToMap(tab)
	tab = tab or {}
	local len = #tab
	local result = {}
	for i = 1, len, 2 do
		result[tab[i]] = tab[i + 1]
	end
	return result
end

function table.clear(tab)
	for k, _ in pairs(tab) do
		tab[k] = nil
	end
end

function table.numbers(tab)
	local count = 0
	for k, _ in pairs(tab) do
		count = count + 1
	end
	return count
end