求单链表是否带环，和环长

//带环返回1

//不带环返回0

int IsCycle(PLinkList pList, PLinkList*ppMeetNode)

{

Node*fast = pList;

Node*slow = pList;

while (fast&&fast->next)

{

slow = slow->next;

fast = fast->next->next;

if (slow == fast)

{

*ppMeetNode = slow;

return 1;

}

}

*ppMeetNode = NULL;

return 0;

}

int GetCycleLength(PLinkList pMeetNode)

{

assert(pMeetNode);

Node*begin = pMeetNode;

int count = 1;

assert(pMeetNode);

while (begin)

{

if (begin->next == pMeetNode)

{

return count;

}

begin = begin->next;

++count;

}

return 0;

}

求单链表是否带环，和环长

原文：http://10622551.blog.51cto.com/10612551/1689605