程序链表约瑟夫问题~~求指教~~~~~~~~~~~~~~~~~~~~~~~~~~~~
程序如下：
程序代码：#include
#include
#define MAX_NODE_NUM 100
#define TRUE 1U
#define FALSE 0U
typedef struct NodeType
{
int id;
int cipher;
struct NodeType *next;
} NodeType;
/* 创建单向循环链表 */
static void CreaList(NodeType **, const int);
/* 运行"约瑟夫环"问题 */
static void StatGame(NodeType **, int);
/* 打印循环链表 */
static void PrntList(const NodeType *);
/* 得到一个结点 */
static NodeType *GetNode(const int, const int);
/* 测试链表是否为空, 空为TRUE，非空为FALSE */
static unsigned EmptyList(const NodeType *);
int main(void)
{
int n, m;
NodeType *pHead = NULL;
while (1)
{
printf("请输入人数n（最多%d个）: ", MAX_NODE_NUM);
scanf("%d", &n);
printf("和初始密码m: ");
scanf("%d", &m);
if (n > MAX_NODE_NUM)
{
printf("人数太多，请重新输入！\n");
continue;
}
else
break;
}
CreaList(&pHead, n);
printf("\n------------ 循环链表原始打印 -------------\n");
PrntList(pHead);
printf("\n-------------删除出队情况打印 -------------\n");
StatGame(&pHead, m);
}
static void CreaList(NodeType **ppHead, const int n)
{
int i, iCipher;
NodeType *pNew, *pCur;
for (i = 1; i <= n; i++)
{
printf("输入第%d个人的密码: ", i);
scanf("%d", &iCipher);
pNew = GetNode(i, iCipher);
if (*ppHead == NULL)
{
*ppHead = pCur = pNew;
pCur->next = *ppHead;
}
else
{
pNew->next = pCur->next;
pCur->next = pNew;
pCur = pNew;
}
}
printf("完成单向循环链表的创建!\n");
}
static void StatGame(NodeType **ppHead, int iCipher)
{
int iCounter, iFlag = 1;
NodeType *pPrv, *pCur, *pDel;
pPrv = pCur = *ppHead;
/* 将pPrv初始为指向尾结点，为删除作好准备 */
while (pPrv->next != *ppHead)
pPrv = pPrv->next;
while (iFlag)
{
for (iCounter = 1; iCounter < iCipher; iCounter++)
{
pPrv = pCur;
pCur = pCur->next;
}
if (pPrv == pCur)
iFlag = 0;
pDel = pCur; /* 删除pCur指向的结点，即有人出列 */
pPrv->next = pCur->next;
pCur = pCur->next;
iCipher = pDel->cipher;
printf("第%d个人出列, 密码: %d\n", pDel->id, pDel->cipher);
free(pDel);
}
*ppHead = NULL;
getchar();
}
static void PrntList(const NodeType *pHead)
{
const NodeType *pCur = pHead;
if (EmptyList(pHead))
return;
do
{
printf("第%d个人, 密码: %d\n", pCur->id, pCur->cipher);
pCur = pCur->next;
}
while (pCur != pHead);
getchar();
}
static NodeType *GetNode(const int iId, const int iCipher)
{
NodeType *pNew;
pNew = (NodeType *)malloc(sizeof(NodeType));
if(!pNew)
{
printf("Error, the memory is not enough!\n");
exit(-1);
}
pNew->id = iId;
pNew->cipher = iCipher;
pNew->next = NULL;
return pNew;
}
static unsigned EmptyList(const NodeType *pHead)
{
if(!pHead)
{
printf("The list is empty!\n");
return TRUE;
}
return FALSE;
}
函数CreaList里面的else{}中pNew赋给了pCur->next后为什么还要赋给pCur？求指教！！
