64 lines
822 B
Go
64 lines
822 B
Go
package main
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import "fmt"
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/**
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* Definition for singly-linked list.
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*/
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type ListNode struct {
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Val int
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Next *ListNode
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}
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func swapPairs(head *ListNode) *ListNode {
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ret := ListNode{0, head}
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ptr := &ret
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for ptr != nil {
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ptrN := ptr.Next
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if ptrN == nil {
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break
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}
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ptrNN := ptrN.Next
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if ptrNN == nil {
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break
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}
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ptrNNN := ptrNN.Next
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ptr, ptrNN.Next, ptr.Next, ptrN.Next = ptrN, ptrN, ptrNN, ptrNNN
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}
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return ret.Next
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}
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func main() {
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head := &ListNode{
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Val: 1,
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Next: &ListNode{
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Val: 2,
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Next: &ListNode{
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Val: 3,
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Next: &ListNode{
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Val: 4,
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Next: &ListNode{
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Val: 5,
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Next: &ListNode{
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Val: 6,
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Next: nil,
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},
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},
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},
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},
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},
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}
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head = swapPairs(head)
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for ptr := head; ptr != nil; ptr = ptr.Next {
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fmt.Println(ptr.Val)
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}
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}
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