🎉 feat: initial commit for leetcode 23 using Swift

Author: liuchuo

Swift/23. Merge k Sorted Lists.swift

@@ -0,0 +1,28 @@
+// 23. Merge k Sorted Lists
+// 80 ms, 90.77%
+func mergeKLists(_ lists: [ListNode?]) -> ListNode? {
+    var i = 0, j = 0, fl = lists.compactMap({$0}), n = fl.count, p: ListNode?
+    if n < 1 { return nil }
+
+    var arr = Array(repeating: 0, count: 256*256)
+    while i < n {
+        p = fl[i]; i += 1
+        while let p1 = p {
+            arr[j] = p1.val
+            p = p1.next; j += 1
+            if p == nil, i < n {
+                p1.next = fl[i]
+            }
+        }
+    }
+
+    arr = Array(arr[..<j]).sorted()
+
+    i = 0; p = fl[0]
+    while let q = p, i < j {
+        q.val = arr[i]
+        p = q.next; i += 1
+    }
+
+    return fl[0]
+}