合并两个有序链表

[Clear2]

因为原始两个链表都是有序的！ 所以题目就很简单了

type ListNode struct {
	Value int
	Next *ListNode
}
func mergeTwoLists(l1 *ListNode, l2 *ListNode) *ListNode {
	prehead := &ListNode{}
	prev := prehead

	for l1 != nil && l2 != nil {
		if l1.Value <= l2.Value {
			prev.Next = l1
			l1 = l1.Next
		} else {
			prev.Next = l2
			l2 = l2.Next
		}
		prev = prev.Next
	}
	if l1 == nil {
		prev.Next = l2
	}
	if l2 == nil {
		prev.Next = l1
	}
	return prehead.Next
}

[Clear2]

测试代码

func main() {
	node1 := new(ListNode)
	node1.Value = 1
	node2 := new(ListNode)
	node2.Value = 2
	node3 := new(ListNode)
	node3.Value = 4
	node1.Next = node2
	node2.Next = node3

	node4 := new(ListNode)
	node4.Value = 1
	node5 := new(ListNode)
	node5.Value = 3
	node6 := new(ListNode)
	node6.Value = 4
	node4.Next = node5
	node5.Next = node6

 	node7 := mergeTwoLists(node1, node4)
	PrintNode(node7)

}