Leetcode 24 Swap Nodes in Pairs

jiajionline · Nov 10, 2023 · dbfb90d · dbfb90d
1 parent cb8b064
commit dbfb90d
Showing 1 changed file with 15 additions and 0 deletions.
diff --git a/0024_Swap Nodes in Pairs/SwapNodesinPaires_Iteration3.java b/0024_Swap Nodes in Pairs/SwapNodesinPaires_Iteration3.java
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+class Solution {
+    public ListNode swapPairs(ListNode head) {
+        ListNode preHead = new ListNode(-1);
+        preHead.next = head;
+        ListNode p = preHead;
+        while(p != null && p.next != null && p.next.next != null) {
+            ListNode next = p.next;
+            p.next = next.next;
+            next.next = p.next.next;
+            p.next.next = next;
+            p = next;
+        }
+        return preHead.next;
+    }
+}