[Leetcode] 024. Swap Nodes in Pairs (Medium) (C++/python)

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Github:https://github.com/illuz/leetcode

024. Swap Nodes in Pairs (Medium) links：

Title: https://oj.leetcode.com/problems/swap-nodes-in-pairs/
Code (GitHub): Https://github.com/illuz/leetcode

Test Instructions：

Swap each pair of nodes in a list (not just the value).

Analysis：

Direct simulation can be done.
It would be convenient to open a front node to do it.
It is convenient to use Python for exception handling and assignment.

Code：

C++:

Class Solution {public:    listnode *swappairs (ListNode *head) {ListNode *newhead = new ListNode (0); Newhead->next = h ead ListNode *prenode = newhead, *curnode = head;int cnt = 1;while (Curnode! = NULL && Curnode->next! = null) {//S WAP Curnode and curnode->nextprenode->next = Curnode->next;curnode->next = prenode->next->next; Prenode->next->next = curnode;//go over the Nodesprenode = Curnode;curnode = Curnode->next;} Head = Newhead->next;delete newhead;return head;    };

Python:

Class solution:    # @param a listnode    # @return a listnode    def swappairs (self, head):        dummy = listnode (0) 
   dummy.next = head        cur = dummy        try:            while True:                Pre, cur, NXT = cur, cur.next, Cur.next.next                # Chang E The position of cur and nxt                pre.next, cur.next, Nxt.next = NXT, nxt.next, cur # now cur are in the                third place< C12/>except:            return Dummy.next

[Leetcode] 024. Swap Nodes in Pairs (Medium) (C++/python)