PROBLEM DESCRIPTION
Given the head of a singly linked list, the task is to check if the linked list has a loop. A loop means that the last node of the linked list is connected back to a node in the same list. So if the next of the last node is null. then there is no loop.
SOLUTION
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class Solution {
public static boolean detectLoop(Node head) {
if(head == null || head.next == null)
return false;
Node slow = head;
Node fast = head.next;
while(fast != null && fast.next != null){
fast = fast.next.next;
slow = slow.next;
if(slow == fast)
return true;
}
return false;
}
}