Adding 2 linklists

Provided 2 linklist which represent numbers in reverse order.Add the 2 linklist and let the result also be in reverse order.
Ex:
representing 111321 and 543 in reverse order using linklist
1->2->3->1->1->1
3->4->5
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4->6->8->1->1->1
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[gist https://gist.github.com/vishnujayvel/5888524]