https://www.geeksforgeeks.org/problems/circular-linked-list/1?itm_source=geeksforgeeks&itm_medium=article&itm_campaign=practice_card
class Solution {
    boolean isCircular(Node head) {
        // Your code here
        if(head.next==null){
            if(head.next==head){
                return true;
            }else{
                return false;
            }
        }
        Node temp=head.next;
        
        while( temp.next!=null){
            if(temp==head)
            return true;
            temp=temp.next;
        }
        return false;
    }
}
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