34 lines
424 B
Go
34 lines
424 B
Go
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package shared
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type Stack struct {
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head *Node
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}
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func (s *Stack) Push(item string) {
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if s.head == nil {
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s.head = &Node{
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Value: item,
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Next: nil,
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}
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} else {
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s.head = &Node{
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Value: item,
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Next: s.head,
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}
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}
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}
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func (s *Stack) Pop() string {
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node := s.Peek()
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s.head = node.Next
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return node.Value
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}
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func (s *Stack) Peek() (node *Node) {
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node = s.head
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if node == nil {
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node = &Node{}
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}
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return
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}
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