A tentative approach to 001--single-link list inversion

The reversal problem of single-linked list is a very basic problem. The topics are as follows:
There is a single-linked list 1->2->3->4->5->6 inverted after the linked list is: 6->5->4->3->2->1.

Method One

Resolution: You can use the three pointer pre to temp,next the node by one. The detailed process is as follows:
(4) Initial state

pre = head;tmp = head->next;pre->nextnull;

(2) First cycle:

next = tmp->next;tmp->next = pre;

The pre and TMP move back one bit, the first loop ends, and the first node points to the head node.

pre = tmp;tmp = next;

(3) Second cycle

next = tmp->next;tmp->next = pre;

pre = tmp;tmp = next;

(4) This loop continues until the last node is reversed.

The specific code is as follows:

linklistReverselinklist (linklistHead) {if(Head = =NULL|| Head->Next==NULL)returnHead//Create three auxiliary pointer pre,tmp,NextlinklistPre,tmp,Next;//Initialize Pre, Tmppre = Head;tmp = head->Next;p re->Next=NULL;//Start traversal while(TMP! =NULL){Next= tmp->Next; Tmp->Next= Pre;    PRE = TMP; TMP =Next;! [Write a description of the picture here] (http://img.blog.csdn.net/20151016235255459)}head = pre;returnHead;}

Method Two

Parse: From the 2nd node to the nth node, after each node is inserted into the 1th node (head node), the first node is finally moved to the footer of the new table.
(1) Initial state

p = head->next;

(2) Start the cycle. The first loop inserts node 3 after Node 1 (steps in the code that correspond to each)

while(p->next){  q = p->next;  (1) p->next =q->next;  (2) q->next = head->next;  (3) head->next = q;}

(3) Add the first node to the tail of the list

    （1）p->next=head;//相当于成环     （2）head=p->next->next;//新head变为原head的next         p->next->next=NULL;//

The specific code is as follows:

Linklist reverselinklist (linklist head) {if(Head== NULL ||Head -Next== NULL)returnHead Linklist p,q;p=Head -Next//Start traversal while(p -Next) {Q=P -Next P -Next=Q -Next Q -Next=Head -Next Head -Next=Q;} P -Next=Head//equivalent to loopingHead=P -Next -Next//new head becomes the next of the original headP -Next -Next=NULL;//Break off ring    returnHead }

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A tentative approach to 001--single-link list inversion