ZJU PAT 1009 Product of Polynomials

从这贴开始不贴题目了，贴个链接吧 http://pat.zju.edu.cn/contests/pat-practise/1009

1002题的改进版，加法变乘法

 1 def ParseList(list):
 2     dict = {}
 3     for j in range(int(list[0])):
 4         a = int(list[j*2+1])
 5         b = float(list[j*2+2])
 6         dict[a] = b
 7     return dict
 8 dict1 = ParseList(raw_input().split())
 9 dict2 = ParseList(raw_input().split())
10 dict = {}
11 for k, v in dict1.iteritems():
12     for x, y in dict2.iteritems():
13         a = k + x
14         b = v * y
15         if a in dict.keys():
16             dict[a] = dict[a]+b
17             if abs(dict[a]) < 0.00001:
18                 del(dict[a])
19         else:
20             dict[a] = b            
21 print len(dict),
22 items = dict.keys()
23 items.sort()
24 for item in reversed(items):
25 print "%d %.1f" % (item, dict[item]),

 

posted @ 2013-01-17 22:55  S.Zhang  阅读(231)  评论(0)  编辑  收藏  举报