the core is prev pointer is storing the current
while(current){
next = current.next
current.next = prev
prev = current
current = next
}
let discuss the part
[0,1,2,3,4]
**prev = null
current = {data:0,next:1}
next = null**
saving current.next in next (later use)
current = {data:0,next:1} current.next contains {data:1,next:2} current.next = prev {null} now current modified {data:0,next:1} to {data:0,next:null} prev = current so prev is null to {data:0,next:null} current = next // now next stores the {data:1,next:2} // next iteration
current = {data:1,next:2} next = current.next {data:2,next:3} current.next = prev {data:0,next:null} now current has {data:1,next:{data:0,next:null}} prev = current //{data:0,next:null} to {data:1,next:{data:0,next:null}} current = next {data:2,next:3} //third iteration
current = {data:2,next:3} next = current.next {data:3,next:4} current.next = prev {data:1,next:{data:0,next:null}} current has {data:2,next:{data:1,next:{data:0,next:null}} prev = current {data:1,next:{data:0,next:null}} to {data:2,next:{data:1,next:{data:0,next:null}} current = next {data:3,next:4}
//fourth iteration
current = {data:3,next:4} next = current.next {data:4,next:null} current.next = prev {data:2,next:{data:1,next:{data:0,next:null}} current has {data:3,next:{data:2,next:{data:1,next:{data:0,next:null}}} prev = current {data:2,next:{data:1,next:{data:0,next:null}} to {data:3,next:{data:2,next:{data:1,next:{data:0,next:null}}} current = next {data:4,next:null}
//last iteration
current = {data:4,next:null} next = current.next {null} current.next = prev {data:3,next:{data:2,next:{data:1,next:{data:0,next:null}}} current become {data:4,next:{data:3,next:{data:2,next:{data:1,next:{data:0,next:null}}}} prev = current current = next completed
happy great coding
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