mirror of
https://github.com/chefyuan/algorithm-base.git
synced 2024-11-28 06:48:53 +00:00
添加py,提供另一种解法
This commit is contained in:
parent
b48730dd5b
commit
ea1335f661
@ -25,11 +25,9 @@
|
||||
|
||||
则我们将 temp 指针指向 low 节点,此时则完成了反转。
|
||||
|
||||
反转之后我们继续反转下一节点,则
|
||||
反转之后我们继续反转下一节点,则 low = temp 即可。然后重复执行上诉操作直至最后,这样则完成了反转链表。
|
||||
|
||||
low = temp 即可。然后重复执行上诉操作直至最后,这样则完成了反转链表。
|
||||
|
||||
我们下面看代码吧
|
||||
我们下面看代码吧。
|
||||
|
||||
我会对每个关键点进行注释,大家可以参考动图理解。
|
||||
|
||||
@ -45,11 +43,6 @@ class Solution {
|
||||
if (head == null || head.next == null) {
|
||||
return head;
|
||||
}
|
||||
//反转
|
||||
return reverse(head);
|
||||
}
|
||||
public ListNode reverse (ListNode head) {
|
||||
|
||||
ListNode low = null;
|
||||
ListNode pro = head;
|
||||
while (pro != null) {
|
||||
@ -64,28 +57,32 @@ class Solution {
|
||||
}
|
||||
return low;
|
||||
}
|
||||
|
||||
}
|
||||
```
|
||||
JS Code:
|
||||
```javascript
|
||||
var reverseList = function(head) {
|
||||
//特殊情况
|
||||
if(!head || !head.next) {
|
||||
return head;
|
||||
}
|
||||
let low = null;
|
||||
let pro = head;
|
||||
while (pro) {
|
||||
//代表橙色指针
|
||||
let temp = pro;
|
||||
//移动绿色指针
|
||||
pro = pro.next;
|
||||
//反转节点
|
||||
temp.next = low;
|
||||
//移动黄色指针
|
||||
low = temp;
|
||||
}
|
||||
return low;
|
||||
};
|
||||
```
|
||||
|
||||
C++代码
|
||||
C++ Code:
|
||||
|
||||
```cpp
|
||||
class Solution {
|
||||
@ -95,11 +92,6 @@ public:
|
||||
if (head == nullptr || head->next == nullptr) {
|
||||
return head;
|
||||
}
|
||||
//反转
|
||||
return reverse(head);
|
||||
}
|
||||
ListNode * reverse (ListNode * head) {
|
||||
|
||||
ListNode * low = nullptr;
|
||||
ListNode * pro = head;
|
||||
while (pro != nullptr) {
|
||||
@ -117,6 +109,28 @@ public:
|
||||
};
|
||||
```
|
||||
|
||||
Python Code:
|
||||
|
||||
```py
|
||||
class Solution:
|
||||
def reverseList(self, head: ListNode) -> ListNode:
|
||||
//特殊情况
|
||||
if head is None or head.next is None:
|
||||
return head
|
||||
low = None
|
||||
pro = head
|
||||
while pro is not None:
|
||||
# 代表橙色指针
|
||||
temp = pro
|
||||
# 移动绿色指针
|
||||
pro = pro.next
|
||||
# 反转节点
|
||||
temp.next = low
|
||||
# 移动黄色指针
|
||||
low = temp
|
||||
return low
|
||||
```
|
||||
|
||||
上面的迭代写法是不是搞懂啦,现在还有一种递归写法,不是特别容易理解,刚开始刷题的同学,可以只看迭代解法。
|
||||
|
||||
|
||||
@ -148,11 +162,17 @@ class Solution {
|
||||
JS Code:
|
||||
```javascript
|
||||
var reverseList = function(head) {
|
||||
//结束条件
|
||||
if (!head || !head.next) {
|
||||
return head;
|
||||
}
|
||||
//保存最后一个节点
|
||||
let pro = reverseList(head.next);
|
||||
//将节点进行反转。我们可以这样理解 4.next.next = 4;
|
||||
//4.next = 5;
|
||||
//则 5.next = 4 则实现了反转
|
||||
head.next.next = head;
|
||||
//防止循环
|
||||
head.next = null;
|
||||
return pro;
|
||||
};
|
||||
@ -181,3 +201,41 @@ public:
|
||||
};
|
||||
```
|
||||
|
||||
Python Code:
|
||||
|
||||
```py
|
||||
class Solution:
|
||||
def reverseList(self, head: ListNode) -> ListNode:
|
||||
# 结束条件
|
||||
if head is None or head.next is None:
|
||||
return head
|
||||
# 保存最后一个节点
|
||||
pro = self.reverseList(head.next)
|
||||
# 将节点进行反转。我们可以这样理解 4->next->next = 4;
|
||||
# 4->next = 5;
|
||||
# 则 5->next = 4 则实现了反转
|
||||
head.next.next = head
|
||||
# 防止循环
|
||||
head.next = None
|
||||
return pro
|
||||
```
|
||||
|
||||
<br/>
|
||||
|
||||
> 贡献者[@jaredliw](https://github.com/jaredliw)注:
|
||||
>
|
||||
> 这里提供一个比较直观的递归写法供大家参考。
|
||||
>
|
||||
> ```py
|
||||
> class Solution:
|
||||
> def reverseList(self, head: ListNode, prev_nd: ListNode = None) -> ListNode:
|
||||
> # 结束条件
|
||||
> if head is None:
|
||||
> return prev_nd
|
||||
> # 记录下一个节点并反转
|
||||
> next_nd = head.next
|
||||
> head.next = prev_nd
|
||||
> # 给定下一组该反转的节点
|
||||
> return self.reverseList(next_nd, head)
|
||||
> ```
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user