Update evaluate_reverse_polish_notation.py

yingl · web-flow · commit 6bd4b1f501dc · 2017-04-25T18:32:21.000+08:00
diff --git a/evaluate_reverse_polish_notation.py b/evaluate_reverse_polish_notation.py
@@ -1,4 +1,4 @@
-# -*- coding: utf-8 -*-
+# coding: utf-8
 
 class Solution:
     # @param {string[]} tokens The Reverse Polish Notation
@@ -28,4 +28,6 @@ def evalRPN(self, tokens):
         return 0 if not ret else ret[0]
 
     def isOperator(self, item):
-        return (item == '+') or (item == '-') or (item == '*') or (item == '/')
+        return (item == '+') or (item == '-') or (item == '*') or (item == '/')
+
+# medium: http://lintcode.com/zh-cn/problem/evaluate-reverse-polish-notation/
