BM3 链表中的节点每k个一组翻转

bm/src/main/java/com/huangge1199/nowcoder/bm/BM3/Solution.java

@@ -0,0 +1,37 @@
+package com.huangge1199.nowcoder.bm.BM3;
+
+import com.huangge1199.nowcoder.common.ListNode;
+
+/**
+ * @author hyy
+ * @Classname Solution
+ * @Description BM3 链表中的节点每k个一组翻转
+ * @Date 2022/7/26 16:12
+ */
+public class Solution {
+    /**
+     * @param head ListNode类
+     * @param k    int整型
+     * @return ListNode类
+     */
+    public ListNode reverseKGroup(ListNode head, int k) {
+        // write code here
+        ListNode cur = head;
+        ListNode pre = null;
+        ListNode tail = head;
+        for (int i = 0; i < k; i++) {
+            if (tail == null) {
+                return head;
+            }
+            tail = tail.next;
+        }
+        for (int i = 0; i < k; i++) {
+            ListNode tmp = cur.next;
+            cur.next = pre;
+            pre = cur;
+            cur = tmp;
+        }
+        head.next = reverseKGroup(tail, k);
+        return pre;
+    }
+}