C鏈表模擬漢諾塔

C鏈表模擬漢諾塔

/*
*鏈表實現漢諾塔——2019.11.26
*/

#include <stdio.h> 
#include <stdlib.h>

typedef struct node
{
    int data;
    struct node *next;
}Node;
/*
*data存儲盤子大小
*/

void output(Node *list)
{
    Node *p = list->next;
    while(p)
    {
        printf("%d ", p->data);
        p = p->next;
    }
    printf("\n");
}

void create(Node **list)
{
    Node* node = (Node *)malloc(sizeof(Node));
    node->next = NULL;
    *list = node;
}

void release(Node **list)
{
    Node *q = NULL;
    Node *p = (*list)->next;

    while(p)
    {
        q = p;
        p = p->next;
        free(q);
    }

    free(*list);
    *list = NULL;
}

void push_back(Node *list, int data)
{
    Node *node = (Node*)malloc(sizeof(Node));
    node->data = data;
    node->next = NULL;

    Node *p = list;
    while(p->next)
        p = p->next;
       
    p->next = node;
}

void push_back(Node *list, Node *node)
{
    Node *p = list;
  
    while(p->next)
        p = p->next;
    p->next = node;
    
    node->next = NULL;
}

Node* pop_back(Node *list)
{
    Node *q = list;
    Node *p = list->next;
    if(p == NULL)
    {
        return NULL;
    } 
    else
    {
        while(p->next)
        {
            q = p;
            p = p->next;
        }
        q->next = NULL;
    
        return p;
    }
}

void move(Node *listFrom, Node *listTo)
{
    Node *p = pop_back(listFrom);
    if(p)        
    {
        push_back(listTo, p);
    }
}

void Hanoi(int n,Node *listA, Node *listB, Node *listC)
{
    if(n == 1)
    {
        move(listA, listC);
    }
    else
    {
        Hanoi(n-1, listA, listC, listB);
        move(listA, listC);
        Hanoi(n-1, listB, listA, listC);
    }
}

int main()
{
    Node *listA;
    Node *listB;
    Node *listC;
 
    create(&listA);
    create(&listB);
    create(&listC);
    
 
    for(int i = 0; i < 5; i++)
    {
       push_back(listA, 5-i);
    }
    printf("A: ");
    output(listA);

    Hanoi(5, listA, listB, listC);

    printf("C: ");
    output(listC); 

    release(&listA);
    release(&listB);
    release(&listC);

    return 0;
}