comefrom: <garvit244>1003_1.py
code: def isValid( S):
      stack = []
      if not S:
          return False
      
      for char in S:
          if char == 'a':
              stack.append('a')
          if char == 'b':
              if not stack:
                  return False
              if stack[-1] == 'a':
                  stack.pop()
                  stack.append(char)
          if char == 'c':
              if not stack:
                  return False
              if stack[-1] == 'b':
                  stack.pop()
      return len(stack) == 0
masked: def sample_funcname ( var_0 ) :
      var_1 = [ ]
      if not var_0 :
          return False
      for var_3 in var_0 :
          if var_3 == 'a' :
              var_1.append ( 'a' )
          if var_3 == 'b' :
              if not var_1 :
                  return False
              if var_1 [ - 1 ] == 'a' :
                  var_1.pop ( )
                  var_1.append ( var_3 )
          if var_3 == 'c' :
              if not var_1 :
                  return False
              if var_1 [ - 1 ] == 'b' :
                  var_1.pop ( )
      return len ( var_1 ) == 0
  