求个关于链表释放的问题 。
写了一个用链表输出1-N之间素数的程序 结果应该没错 但是在释放删除结点和遍历释放时出错了可是俺不知道怎么改 求大牛指教。
程序代码：/*
Print the prime numbers between 1-N
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#define N 1000
#define M (int)sqrt((double)N)
typedef struct Node
{
int num;
struct Node *next;
}SNode, *LinkList;
LinkList CreateList(LinkList head);
void PrintPrime(LinkList head);
LinkList GetPrimes(LinkList head);
void FreeList(LinkList head);
int main(void)
{
LinkList head = NULL;
head = CreateList(head);
GetPrimes(head);
PrintPrime(head);
//FreeList(head); 加这个会出错
return 0;
}
LinkList CreateList(LinkList head)
{
LinkList p, q;
if (NULL == head)
{
head = (LinkList)malloc(sizeof(LinkList));
if (NULL == head)
{
printf("Memory allocation error!\n");
return NULL;
}
}
head->next = NULL;
p = (LinkList)malloc(sizeof(LinkList));
if (NULL == p)
{
printf("Memory allocation error!\n");
return NULL;
}
p->num = 2;
head->next = p;
p->next = NULL;
int i;
for (i = 3; i <= N; i += 2)
{
q = (LinkList)malloc(sizeof(LinkList));
if (NULL == q)
{
printf("Memory allocation error!\n");
return NULL;
}
q->num = i;
q->next = p->next;
p->next = q;
p = p->next;
}
return head;
}
void PrintPrime(LinkList head)
{
LinkList p;
int count = 0;
if (NULL == head || NULL == head->next)
{
printf("This is an empty linklist!\n");
return;
}
p = head->next;
while (NULL != p)
{
printf("%-6d", p->num);
p = p->next;
count++;
if (0 == count % 10)
printf("\n");
if (0 == count %200)
getchar();
}
printf("\nThere are %d prime nunbers.\n", count);
}
LinkList GetPrimes(LinkList head)
{
LinkList p, pre, div;
div = head->next->next;
while (div->num <= M)
{
pre = div;
p = div->next;
while (NULL != p)
{
if (0 == ((p->num) % (div->num)))
{
pre->next = p->next;
//free(p); 加这个也会错
p = pre->next;
}
else
{
pre = pre->next;
p = p->next;
}
}
div = div->next;
}
return head;
}
////// 难道我释放函数写错了 貌似没问题啊
void FreeList(LinkList head)
{
LinkList p;
if (NULL == head)
return;
else
{
while (NULL != head)
{
p = head;
head = head->next;
free(p);
}
}
}百分求解 [ 本帖最后由 有容就大 于 2012-11-26 23:19 编辑 ]
