如何仅使用两个内存位置来确定链表是否具有循环

我建议使用

Floyd's Cycle-Finding Algorithm

Tortoise and the HareAlgorithm

示例代码：

function boolean hasLoop(Node startNode){  Node slowNode = Node fastNode1 = Node fastNode2 = startNode;  while (slowNode && fastNode1 = fastNode2.next() && fastNode2 = fastNode1.next()){    if (slowNode == fastNode1 || slowNode == fastNode2) return true;    slowNode = slowNode.next();  }  return false;}

有关Wikipedia的更多信息：Floyd的循环查找算法。