From 21e4c0e93e11f7a2614a4dfbe4af8c201a3f03b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=9E=81=E5=AE=A2=E5=AD=A6=E4=BC=9F?= <qxuwei@yeah.net>
Date: Tue, 24 Aug 2021 13:28:37 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20142.=E7=8E=AF=E5=BD=A2?=
 =?UTF-8?q?=E9=93=BE=E8=A1=A8II=20Swift=E7=89=88=E6=9C=AC?=
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---
 problems/0142.环形链表II.md | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/problems/0142.环形链表II.md b/problems/0142.环形链表II.md
index 91e14e27..4a3f36b0 100644
--- a/problems/0142.环形链表II.md
+++ b/problems/0142.环形链表II.md
@@ -296,6 +296,39 @@ var detectCycle = function(head) {
 };
 ```
 
+Swift:
+```swift
+class Solution {
+    func detectCycle(_ head: ListNode?) -> ListNode? {
+        var slow: ListNode? = head
+        var fast: ListNode? = head
+        while fast != nil && fast?.next != nil {
+            slow = slow?.next
+            fast = fast?.next?.next
+            if slow == fast {
+                // 环内相遇
+                var list1: ListNode? = slow
+                var list2: ListNode? = head
+                while list1 != list2 {
+                    list1 = list1?.next
+                    list2 = list2?.next
+                }
+                return list2
+            }
+        }
+        return nil
+    }
+}
+extension ListNode: Equatable {
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(val)
+        hasher.combine(ObjectIdentifier(self))
+    }
+    public static func == (lhs: ListNode, rhs: ListNode) -> Bool {
+        return lhs === rhs
+    }
+}
+```
 
 -----------------------
 * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)