데이터 구조 학습 노트 1 - 링크 반전 (재 귀 와 비 재 귀)

//============================================================================
// Name        :     .cpp
// Author      : Gaotong
// Version     :
// Copyright   : www.acmerblog.com
// Description : Hello World in C++, Ansi-style
//============================================================================

#include
#include

/*      */
struct node
{
    int data;
    struct node* next;
};

/*      .    3   ，     ，  ，    */
static void reverse(struct node** head_ref)
{
    struct node* prev   = NULL;
    struct node* current = *head_ref;
    struct node* next;
    while (current != NULL)
    {
        next  = current->next;
        current->next = prev;
        prev = current;
        current = next;
    }
    *head_ref = prev;
}

/*     。      */
void push(struct node** head_ref, int new_data)
{
    struct node* new_node =
            (struct node*) malloc(sizeof(struct node));

    new_node->data  = new_data;
    new_node->next = (*head_ref);
    (*head_ref)    = new_node;
}

/*      */
void printList(struct node *head)
{
    struct node *temp = head;
    while(temp != NULL)
    {
        printf("%d  ", temp->data);
        temp = temp->next;
    }
}

int main()
{
    struct node* head = NULL;

     push(&head, 20);
     push(&head, 4);
     push(&head, 15);
     push(&head, 85);
     push(&head, 60);
     push(&head, 100);

     printList(head);
     reverse(&head);
     printf("
 Reversed Linked list 
");
     printList(head);

}

/*         */
static struct node * reverseRecall(struct node* head){
    //              
    if(NULL == head || head->next == NULL) return head;
    //head->next        
    struct node * newHead = reverseRecall(head->next);
    head->next->next = head; //    
    head->next = NULL;//       next     
    return newHead;
}