remove solution for test fix PR

Author: gmstanle

epi_judge_python/is_list_cyclic.py

@@ -8,53 +8,7 @@
 
 
 def has_cycle(head: ListNode) -> Optional[ListNode]:
-    """Return None if there is no cycle, or the node at the start
-    of the cycle if there is a cycle."""
-    
-    # If list has only 1 element, no cycle.
-    if not head:
-        return None
-    if not head.next:
-        return None
-    
-    # Slow and fast node.
-    slow, fast = head, head
-    i = 0
-    while fast.next and fast.next.next:
-        # Move fast up every round.
-        fast = fast.next
-        # Move slow up every other round.
-        if i % 2:
-            slow = slow.next
-        
-        # Detect cycle
-        if fast is slow or fast.next is slow:
-            # We have a cycle!
-            # We can count the length of the cycle in O(n) time by
-            # freezing slow and moving fast until it hits slow again.
-            fast = slow.next
-            cycle_length = 1
-            while fast is not slow:
-                fast = fast.next
-                cycle_length += 1
-            print(cycle_length)
-            
-            # Now that we have cycle length, we just start fast and slow at head.
-            # increment slow after incrementing fast cycle_length times. once 
-            # fast is slow, slow is the start of the cycle.
-            fast, slow = head, head
-            for _ in range(cycle_length):
-                fast = fast.next
-                
-            while fast is not slow:
-                fast = fast.next
-                slow = slow.next
-            
-            return slow
-        
-        i += 1
-    
-    # If we reach the end (fast.next is None).
+    # TODO - you fill in here.
     return None