鏈表實現冒泡排序

#include"stdio.h"
#include"stdlib.h"

typedef struct node
{
    int num;
    struct node *next;
}node;

node *head = NULL;
node *last = NULL;

void print()
{
    node *p = head;
    while( p != NULL)
    {
        printf("%d ",p->num);
	p = p->next;
    }
    printf("\n");
}

void create()
{
    int n = 6;
    node *p;
    while(n)
    {
        p = (node *)malloc( sizeof(node) );
	p->num = rand()%50+1;
	if( head == NULL)
	{
	    head = p;
	    last = p;
	}
	else
	{
	    last->next = p;
	    last = p;
	}
	last->next = NULL;
	n--;
    }
}

void sort()
{
    node *p,*q,*front;
    int i,j,flag;
    if( head == NULL || head->next == NULL)
    {
        return;
    }
    for( i = 0; i < 6 ; i++)
    {
        p = head;
        front = NULL;
	q = p->next;
	flag = 0;
        for( j = 0 ; j < 6-i-1;j++)
	{
	    if( p->num > q->num)
	    {
	        flag++;
	        if(front == NULL)
		{
		    p->next = q->next;
                    q->next = p;
		    head = q;
		}
		else
		{
		    p->next = q->next;
		    q->next = p;
		    front->next = q;
		}
		front = q;
		q = p->next;
	    }
	    else
	    {
	        front = p;
	        p = q;
	        q = p->next;
	    }
	}
	if( flag == 0)
	{
	    break;
	}
    }
}

int main()
{
    printf("正在產生隨機數\n");
    create();
    printf("排序前:\n");
    print();
    sort();
    printf("排序後：\n");
    print();
    return 0;
}