43 lines
1.1 KiB
Swift
43 lines
1.1 KiB
Swift
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/**
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* Definition for singly-linked list.
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* public class ListNode {
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* public var val: Int
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* public var next: ListNode?
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* public init() { self.val = 0; self.next = nil; }
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* public init(_ val: Int) { self.val = val; self.next = nil; }
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* public init(_ val: Int, _ next: ListNode?) { self.val = val; self.next = next; }
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* }
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*/
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class Solution {
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func mergeTwoLists(_ list1: ListNode?, _ list2: ListNode?) -> ListNode? {
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var list1 = list1
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var list2 = list2
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let head = ListNode()
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var node: ListNode? = head
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while list1 != nil && list2 != nil {
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if list1!.val < list2!.val {
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node!.next = list1
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node = node!.next
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list1 = list1!.next
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} else {
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node!.next = list2
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node = node!.next
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list2 = list2!.next
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}
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}
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if list1 != nil {
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node!.next = list1
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}
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if list2 != nil {
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node!.next = list2
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}
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return head.next
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}
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}
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