数据结构 - 判断单链表是否有环（C++）

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/*
 * Created by Chimomo.
 */

#include "SingleLinkedList.h"

template<class T>
bool SingleLinkedList<T>::hasLoop() {
    Node<T> *pNodeSlow = head, *pNodeFast = head;
    while (pNodeFast && pNodeFast->next) {
        pNodeSlow = pNodeSlow->next;
        pNodeFast = pNodeFast->next->next;
        if (pNodeSlow == pNodeFast) {
            break;
        }
    }
    if (pNodeFast == NULL || pNodeFast->next == NULL) {
        return false;
    } else {
        return true;
    }
}