@startuml
title Step 2 — Reverse current->next

object "Node 1" as n1 {
  value = 1
}

object "Node 2" as n2 {
  value = 2
}

object "Node 3" as n3 {
  value = 3
}

n1 --> "null" : next
n2 --> n3 : next
n3 --> "null" : next

object "previous" as prev
object "current" as cur
object "next" as nxt

prev --> "null"
cur --> n1
nxt --> n2

note right of n1
current->next = previous

Node 1 no longer points to Node 2.
It now points to the already reversed part.

At the first iteration, the reversed part is empty,
so Node 1 points to null.
end note

@enduml