BM6 判断链表中是否有环

bm/src/main/java/com/huangge1199/nowcoder/bm/BM6/Solution.java

@@ -0,0 +1,28 @@
+package com.huangge1199.nowcoder.bm.BM6;
+
+import com.huangge1199.nowcoder.common.ListNode;
+
+/**
+ * @author hyy
+ * @Classname Solution
+ * @Description BM6 判断链表中是否有环
+ * @Date 2022/7/26 16:58
+ */
+public class Solution {
+    public boolean hasCycle(ListNode head) {
+        ListNode fast = head;
+        ListNode slow = head;
+        while (fast != null) {
+            fast = fast.next;
+            if (fast == null) {
+                return false;
+            }
+            fast = fast.next;
+            slow = slow.next;
+            if (fast == slow) {
+                return true;
+            }
+        }
+        return false;
+    }
+}