public boolean isPalindrome1(ListNode head) {
		ListNode slowp = head, fastp = head, revp = null;
		while (fastp!=null && fastp.next!=null){
			fastp = fastp.next.next;
			ListNode tmp = slowp.next;
			slowp.next = revp;
			revp = slowp;
			slowp = tmp;
		}
		if (fastp!=null)
			slowp = slowp.next;
		if(log){
			ListNode.printLCLinkedList(slowp);
			ListNode.printLCLinkedList(revp);
		}
		while (slowp!=null && revp!=null ){
			if (slowp.val != revp.val)
				return false;
			slowp = slowp.next;
			revp = revp.next;
		}
		return true;
	}