关于list.remove

jody970214

1. seen = 'A'
   
2. graph = {
   
3.     "A" : ["B", "C"],
   
4.     "B" : ["A", "C", "D"],
   
5.     "C" : ["A", "B", "D", "E"],
   
6.     "D" : ["B", "C", "E", "F"],
   
7.     "E" : ["C", "D"],
   
8.     "F" : ["D"]
   
9. }
   
10. for i in graph:
    
11.     print('')
    
12.     for j in graph[i]:
    
13.         print(j, end = '')
    
14.         if j in seen:
    
15.             graph[i].remove(j)

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小弟尝试以上代码希望将字典中所有的A去除然而结果却不尽人意，结果如下：

1. 
   
2. 
   
3. BC
   
4. AD
   
5. ADE
   
6. BCEF
   
7. CD
   
8. D

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不知道这是这么回事，希望大佬解决一下

一个账号

因为你删除了列表中的元素但没删除 j，把代码改成这样：

1. seen = 'A'
   
2. graph = {
   
3.     "A" : ["B", "C"],
   
4.     "B" : ["A", "C", "D"],
   
5.     "C" : ["A", "B", "D", "E"],
   
6.     "D" : ["B", "C", "E", "F"],
   
7.     "E" : ["C", "D"],
   
8.     "F" : ["D"]
   
9. }
   
10. for i in graph:
    
11.     for j in graph[i]:
    
12.         if j in seen:
    
13.             graph[i].remove(j)
    
14. 
    
15. for value in graph.values():
    
16.     for i in value:
    
17.         print(i, end="")
    
18.     print()

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Hoiste

其实你的问题已经解决了，之所以打印出A是因为你在移除字符'A'之前先执行了print(j, end = '')，所以就原样打印了一遍每个列表的元素，你可以在最后print(graph)看看，已经没有'A'元素在里面了