text: def decompose(n):
      return helper(n, n**2)
  def helper(n, sum, arr=[]):
      if sum==0:
          return arr[::-1]
      for i in range(n-1, -1, -1):
          if i**2<=sum:
              return helper(i, sum-i**2, arr+[i]) or helper(i, sum, arr) 