static void Main(string[] args)
{
SingleLinkNode first = new SingleLinkNode(1);
SingleLinkNode node2 = new SingleLinkNode(2);
SingleLinkNode node3 = new SingleLinkNode(3);
SingleLinkNode node4 = new SingleLinkNode(4);
SingleLinkNode node5 = new SingleLinkNode(5);
SingleLinkNode node6 = new SingleLinkNode(6);
first.Next = node2;
node2.Next = node3;
node3.Next = node4;
node4.Next = node5;
node5.Next = node6;
SingleLinkNode second = new SingleLinkNode(11);
SingleLinkNode node10 = new SingleLinkNode(10);
SingleLinkNode node9 = new SingleLinkNode(9);
SingleLinkNode node8 = new SingleLinkNode(8);
second.Next = node10;
node10.Next = node9;
node9.Next = node8;
node8.Next = node3;
SingleLinkNode crossNode = first.FindCrossNode(second);
Console.WriteLine(crossNode.Data);
}
public SingleLinkNode FindCrossNode(SingleLinkNode secondLinkNode)
{
if (secondLinkNode != null)
{
int currentLength = 0;
int secondLength = 0;
SingleLinkNode first = this;
SingleLinkNode second = secondLinkNode;
while (first != null)
{
currentLength++;
first = first.Next;
}
while (second != null)
{
secondLength++;
second = second.Next;
}
first = this;
second = secondLinkNode;
// 当前的链表比较长，我们先把差值的步数先走掉
// 然后齐步走
if (currentLength > secondLength)
{
int gap = currentLength - secondLength;
while (gap > 0)
{
first = first.Next;
gap--;
}
}
// 先走secondlinknode， 然后齐步走
else
{
int gap = secondLength - currentLength;
while (gap > 0)
{
second = second.Next;
gap--;
}
}
while (first != null && second != null && first != second)
{
first = first.Next;
second = second.Next;
}
if (first == second)
{
return(first);
}
}
return(null);
}