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Merge pull request #795 from pragatiahuja/master

final README

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`@@ -471,6 +471,7 @@ This will print the list like so:`
`471`	`471`
`472`	`472`	`How about reversing a list, so that the head becomes the tail and vice versa? There is a very fast algorithm for that:`
`473`	`473`
	`474`	`+Iterative Approach:`
`474`	`475`	```swift
`475`	`476`	`public func reverse() {`
`476`	`477`	`var node = head`
`@@ -482,6 +483,18 @@ How about reversing a list, so that the head becomes the tail and vice versa? Th`
`482`	`483`	`}`
`483`	`484`	`}`
`484`	`485`	```
	`486`	`+Recursive Approach:`
	`487`	+```swift
	`488`	`+ public func reverse(node: head) {`
	`489`	`+ if !head \|\| !head.next {`
	`490`	`+ return head`
	`491`	`+ }`
	`492`	`+ let temp = reverse(head.next)`
	`493`	`+ head.next.next = head`
	`494`	`+ head.next = nil`
	`495`	`+ return temp`
	`496`	`+ }`
	`497`	+```
`485`	`498`
`486`	`499`	This loops through the entire list and simply swaps the `next` and `previous` pointers of each node. It also moves the `head` pointer to the very last element. (If you had a tail pointer you'd also need to update it.) You end up with something like this:
`487`	`500`

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