feat: add leetcode question with kotlin #25

Author: hi-dhl

00-code(源代码)/src/com/hi/dhl/algorithms/leetcode/_025/kotlin/Solution.kt

@@ -0,0 +1,51 @@
+package com.hi.dhl.algorithms.leetcode._025.kotlin
+
+import com.hi.dhl.algorithms.model.ListNode
+
+/**
+ * <pre>
+ *     author: dhl
+ *     date  : 2022/6/24
+ *     desc  :
+ * </pre>
+ */
+class Solution {
+
+    fun reverseKGroup(head: ListNode?, k: Int): ListNode? {
+        if (head == null) {
+            return head
+        }
+        val len = getListLength(head)
+        val dumpHead = ListNode(0)
+        dumpHead.next = head
+        var p = dumpHead
+        var q = dumpHead.next
+        var index = 0
+        while (q != null) {
+            if (len - index < k) {
+                return dumpHead.next
+            }
+            index = index + k
+            var m = k;
+            while (--m != 0) {
+                val node = q.next
+                q.next = q.next.next
+                node.next = p.next
+                p.next = node
+            }
+            p = q
+            q = q.next
+        }
+        return dumpHead.next
+    }
+
+    private fun getListLength(head: ListNode?): Int {
+        var cur = head
+        var len = 0
+        while (cur != null) {
+            cur = cur?.next
+            len++
+        }
+        return len
+    }
+}