Problem C: 以太网交换机转发数据帧

 1 def MacAdress(m):
 2     ad = []
 3     while m>0:
 4         m-=1
 5         #将一行mac地址拆分进数组a中
 6         a = input().split(" ",3)
 7         ad.append(a)
 8     return ad
 9 
10 def Frame(n):
11     frame = []
12     while n>0:
13         n-=1
14         a = input().split(" ", 4)
15         frame.append(a)
16     return frame
17 
18 #查找Mac表并转发Mac帧
19 def Forward(macad,frame):
20     forward = []
21     for i in frame:
22         purpose = i[0]
23         flag = 0 #表示未找到目的地址，转发ALL
24         port = 0 #定义端口号
25         pur = [] #存放目的地址和转发信息
26         pur.append(purpose) #之后再添加转发信息
27         for j in macad:
28             if purpose == j[0]:
29                 flag = 1 #表示找到转发端口
30                 port = j[1]
31                 break
32         if flag==1:
33             if port == i[2]:
34                 pur.append("NONE")
35                 forward.append(pur)
36                 continue  # 继续循环
37             pur.append(port)
38             forward.append(pur)
39             continue #继续循环
40         #如果MAC地址表中给出的端口就是该帧进入交换机的端口，则应丢弃这个帧
41         pur.append("ALL")
42         forward.append(pur) #没找到转发所有
43 
44     return forward
45 
46 if __name__ == '__main__':
47     m, n = map(int, input().split())
48     #定义两个集合接受函数的返回值
49     macad = MacAdress(m)
50     frame = Frame(n)
51     ans = Forward(macad,frame)
52     for i in ans:
53         print(f"{i[0]:18}{i[1]}")