comefrom: <doocs>0394.Decode String_1.py
code: def decodeString( s: str) -> str:
      s1, s2 = [], []
      num, res = 0, ''
      for c in s:
          if c.isdigit():
              num = num * 10 + int(c)
          elif c == '[':
              s1.append(num)
              s2.append(res)
              num, res = 0, ''
          elif c == ']':
              res = s2.pop() + res * s1.pop()
          else:
              res += c
      return res
masked: def sample_funcname ( var_0 : str ) -> str :
      var_2 , var_3 = [ ] , [ ]
      var_5 , var_7 = 0 , ''
      for var_8 in var_0 :
          if var_8.isdigit ( ) :
              var_5 = var_5 * 10 + int ( var_8 )
          elif var_8 == '[' :
              var_2.append ( var_5 )
              var_3.append ( var_7 )
              var_5 , var_7 = 0 , ''
          elif var_8 == ']' :
              var_7 = var_3.pop ( ) + var_7 * var_2.pop ( )
          else :
              var_7 += var_8
      return var_7
  