The initial state of the chain is pt -> 1 -> 2 -> 3, the nodes are represented by pt, pt.Next, pt.Next.Next and pt.Next.Next.Next.
After the swap, the chain is pt -> 2 -> 1 -> 3, and pt points to 1. We can easily update the variables, point to the new Next in one line.
Signed-off-by: Hanlin Shi shihanlin9@gmail.com
The initial state of the chain is
pt -> 1 -> 2 -> 3, the nodes are represented bypt,pt.Next,pt.Next.Nextandpt.Next.Next.Next. After the swap, the chain ispt -> 2 -> 1 -> 3, andptpoints to1. We can easily update the variables, point to the newNextin one line.