- 网页标题：ocr
- 问题网址：http://www.pythonchallenge.com/pc/def/ocr.html
- 问题描述：问题给了个图片，无意义
- 问题提示：recognize the characters. maybe they are in the book,
but MAYBE they are in the page source. - 问题分析：查看网页源代码，发现“find rare characters in the mess below:”应该是找出下面乱码中最少的字母来，把乱码保存成文件，思路过程是：
- 统计词频
- 利用python中的set统计出有哪些字母，要保证顺序
- 然后计算词频即可
- 代码实现：
def level_2(): # http://www.pythonchallenge.com/pc/def/ocr.html with open('level_2.txt', 'r')as f: l2_content = f.read() origin_list=[x for x in l2_content] ch_list = list(set(l2_content)) ch_list.sort(key=origin_list.index)#按照原来的顺序排序 print ch_list print [l2_content.count(x) for x in ch_list] #分析词频最少的即可其他代码：
def a_level_2(): with open('level_2.txt', 'r') as f: l2_content = f.read() order_dict = collections.OrderedDict() # 保证出现的顺序 for ch in l2_content: order_dict[ch] = order_dict.get(ch, 0) + 1 # get函数犀利 print order_dict pass - 输出结果：
['%', '$', '@', '_', '^', '#', ')', '&', '!', '+', ']', '*', '}', '[', '(', '{', '\n', 'e', 'q', 'u', 'a', 'l', 'i', 't', 'y'] [6104, 6046, 6157, 6112, 6030, 6115, 6186, 6043, 6079, 6066, 6152, 6034, 6105, 6108, 6154, 6046, 1219, 1, 1, 1, 1, 1, 1, 1, 1]对应结果是'e', 'q', 'u', 'a', 'l', 'i', 't', 'y'，然后替换url即可
- 替换网址：http://www.pythonchallenge.com/pc/def/equality.html