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book.leetcode/docs/hard/23.md

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+---
+weight: 23
+
+bookFlatSection: true
+
+BookToC: true
+
+title: "23. 合并 K 个升序链表"
+---
+
+# 23. 合并 K 个升序链表
+
+## 题目地址
+
++ [力扣](https://leetcode.cn/problems/merge-k-sorted-lists/)
++ [LeetCode](https://leetcode.com/problems/merge-k-sorted-lists/)
+
+## 解题思路
+
+## 具体实现
+
+{{< tabs "uniqueid" >}}
+
+{{< tab "Go" >}}
+
+```go
+package main
+
+import (
+	"fmt"
+)
+
+type ListNode struct {
+	Val  int
+	Next *ListNode
+}
+
+func mergeKLists(lists []*ListNode) *ListNode {
+	if len(lists) == 0 {
+		return nil
+	}
+	n := len(lists)
+	return merge(lists, 0, n-1)
+}
+
+func merge(lists []*ListNode, left, right int) *ListNode {
+	if left == right {
+		return lists[left]
+	}
+	mid := left + (right-left)/2
+	l1 := merge(lists, left, mid)
+	l2 := merge(lists, mid+1, right)
+	return mergeTwoLists(l1, l2)
+}
+
+func mergeTwoLists(l1 *ListNode, l2 *ListNode) *ListNode {
+	if l1 == nil {
+		return l2
+	}
+	if l2 == nil {
+		return l1
+	}
+	if l1.Val < l2.Val {
+		l1.Next = mergeTwoLists(l1.Next, l2)
+		return l1
+	} else {
+		l2.Next = mergeTwoLists(l1, l2.Next)
+		return l2
+	}
+}
+
+func main() {
+	list1 := &ListNode{Val: 1, Next: &ListNode{Val: 4, Next: &ListNode{Val: 5}}}
+	list2 := &ListNode{Val: 1, Next: &ListNode{Val: 3, Next: &ListNode{Val: 4}}}
+	list3 := &ListNode{Val: 2, Next: &ListNode{Val: 6}}
+
+	lists := []*ListNode{list1, list2, list3}
+
+	result := mergeKLists(lists)
+
+	for result != nil {
+		fmt.Printf("%d ", result.Val)
+		result = result.Next
+	}
+}
+
+```
+
+{{< /tab  >}}
+
+{{< /tabs  >}}
+
+## 参考
+
++ [合并K个升序链表-解题思路](https://www.bilibili.com/video/BV1QK4y1N7ww)
+