Linked List Reversal Algorithm

Interview question 20: How to reverse a single linked list
(1) Reverse a linked list. Circular Algorithm
Linked list is a basic and commonly used data structure in C. This thing must be mastered proficiently. Reversing a linked list is more troublesome than ordering it. The key is to abstract three things: the previous node, the current node, and the next node
. When a node
has these three things, the algorithm can be performed.
These three things can be understood as data structures, and the other steps are loops and algorithms.

126 //反转一个链表
127 Link* LinkRevert(Link* p){
128     printf("enter function LinkRevert\n");
129     if(p->next == NULL){
130       return p;
131     }
132     Link* pre = p->next;
133     Link* cur = pre->next;
134     Link* behind = cur->next;
135     pre->next = NULL;
136     printf("cur1=%p\n", cur);
137     while(cur)
138     { 
139       printf("cur2=%p\n", cur);
140       cur->next = pre;
141       pre = cur;
142       cur = behind;
143       if(behind)
144       {
145       behind = behind->next;
146       }
147     }
148     p->next = pre;
149     printf("cur3=%p\n", pre);
150     printf("exit function LinkRevert\n");
151     return p;
152 }
153 int main() {
154     Link* p = initLink();
155     printf("初始化链表为：\n");
156     display(p);
157     Link* p2 = LinkRevert(p);
158     display(p2);
159     Link_free(p2);
160     return 0;
161 }

Operation status:

root@mkx:~/learn/link# ./link 
初始化链表为：
enter function displaty
1 2 3 4 
exit function displaty
enter function LinkRevert
cur1=0x22a6050
cur2=0x22a6050
cur2=0x22a6070
cur2=0x22a6090
cur3=0x22a6090
exit function LinkRevert
enter function displaty
4 3 2 1 
exit function displaty
root@mkx:~/learn/link#