40 lines
506 B
Go
40 lines
506 B
Go
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package main
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type Stack struct {
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head *StackNode
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}
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func (s *Stack) Push(item byte) {
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if s.head == nil {
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s.head = &StackNode{
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char: item,
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next: nil,
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}
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} else {
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new := StackNode{
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char: item,
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next: s.head,
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}
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s.head = &new
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}
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}
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func (s *Stack) Pop() byte {
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node := s.Peek()
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s.head = node.next
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return node.char
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}
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func (s *Stack) Peek() (node *StackNode) {
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node = s.head
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if node == nil {
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node = &StackNode{}
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}
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return
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}
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type StackNode struct {
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char byte
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next *StackNode
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}
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