output_description: For each dataset, print the number of combinations in a line.
input_description: The input consists of multiple datasets. For each dataset, two integers n and
  x are given in a line.
  
  The input ends with two zeros for n and x respectively. Your program should
  not process for these terminal symbols.
attempt: # coding: utf-8
  # Here your code !
  
  
  def func():
      data = []
      while True:
          try:
              line = [int(item) for item in input().rstrip().split(" ")]
              if line == [0, 0]:
                  break
              data.append(line)
          except EOFError:
              break
          except:
              return inputError()
  
      left = 1
      numbers = 3
      [print(len(sumcombination(left, line[0], numbers, line[1]))) for line in data]
  
  
  def sumcombination(left, right, numbers, total):
      """
      left ~ right??????????????°??????(numbers)????????´??°???????¨????total?????????????????????????????????????????????
      """
      result = []
      if numbers == 1:
          if (left <= total) and (right >= total):
              result = [total]
          return result
  
      for i in range(left, right + 1):
          if numbers == 2:
              if i >= total - i:
                  break
              elif (i != total - i) and (left <= total - i) and (right >= total - i):
                  result.append([i, total - i])
          elif (len(range(i, right + 1)) < numbers) or (
              sum(range(i + 1, i + numbers)) > total - i
          ):
              break
          elif sum(range(right - numbers + 2, right + 1)) < total - i:
              continue
          else:
              sub = sumcombination(i + 1, right, numbers - 1, total - i)
              if len(sub) > 0:
                  [items.insert(0, i) for items in sub]
                  result.extend(sub)
  
      return result
  
  
  def inputError():
      print("input error")
      return -1
  
  
  func()
  
problem_description: How many ways?
  
    
  
  Write a program which identifies the number of combinations of three integers
  which satisfy the following conditions:
  
    * You should select three distinct integers from 1 to n.
    * A total sum of the three integers is x.
  
  For example, there are two combinations for n = 5 and x = 9.
  
    * 1 + 3 + 5 = 9
    * 2 + 3 + 4 = 9
samples: [{"input": "9\n    0 0", "output": "## Note\n\n      \u89e3\u8aac"}]