移动列表元素 [英] Move elements in list

问题描述

我宣布下列对象

 名单，其中，串＆GT;表= {凯特，约翰，禄，夏娃，雨果};
 

我想移动夏娃在我的名单前面？我怎样才能做到这一点。我不能重新安排其他元素！
在输出我想要得到这个

 夏娃，凯特，约翰，禄，雨果
 

解决方案

  list.Remove（夏娃）; //删除列表中的第一个夏娃元素
list.Insert（0，夏娃）; //插入夏娃在列表中的第一个位置
 

然而，如果你的列表中包含多个夏娃S，要求删除（夏娃）将仅删除了夏娃中第一次出现。

和你要知道，在列表的开头插入的元素是一个昂贵的操作。因为已经在列表的所有元素都被移位。

更新

由于@AlvinWong评论，的LinkedList＆LT;字符串＆GT; 是一个很好的解决方案插入一个元素时，为了避免这种开销。该插入运行在O（1）完成的（O（NI）在列表）。最大的缺点的LinkedList＆LT;字符串＆GT; 是访问我个元素是O（I）的操作（ O（1）在列表）。

I declare following object

List<string> list = {"Kate", "John", "Paul", "Eve", "Hugo"};

I would like to move "Eve" at front of my list? How can I do that. I must not to reorder other elements!
At output I want to get this

"Eve", "Kate", "John", "Paul", "Hugo"

解决方案

list.Remove("Eve");  // Removes the first "Eve" element in the list
list.Insert(0, "Eve");  // Inserts "Eve" at the first position in the list

However, if your list contains multiple "Eve"s, calling Remove("Eve") will only remove the first occurrence of "Eve".

And you have to know that inserting element at the beginning of a list is an expensive operation. Because all elements already in the list have to be shifted.

UPDATE

As @AlvinWong commented, LinkedList<string> is a very good solution to avoid this overhead when inserting an element. The Insert operation is done in O(1) (O(n-i) in a List). The major drawback of LinkedList<string> is that accessing the ith element is an operation in O(i) (O(1) in a List).

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