three_type_parenthesis_valid.py

def isValid(s):
  """
  :type s: str
  :rtype: bool
  """
  if s:
    if len(s) == 1:
      return False
    stack = []
    d = {'[': ']', '(': ')', '{': '}'}
    e = {']', '}', ')'}
    for i in s:
      if i in d:
        stack.append(i)
      elif i in e:
        if len(stack) == 0 or d[stack.pop()] != i:
          return False
      else:
        return False
    return len(stack) == 0
  return False