28 lines
679 B
Go
28 lines
679 B
Go
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// Package collection implements a generic stack.
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package collection
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// The zero value for Stack is an empty stack ready to use.
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type Stack struct {
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data []interface{}
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}
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// Push adds x to the top of the stack.
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func (s *Stack) Push(x interface{}) {
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s.data = append(s.data, x)
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}
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// Pop removes and returns the top element of the stack.
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// It’s a run-time error to call Pop on an empty stack.
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func (s *Stack) Pop() interface{} {
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i := len(s.data) - 1
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res := s.data[i]
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s.data[i] = nil // to avoid memory leak
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s.data = s.data[:i]
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return res
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}
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// Size returns the number of elements in the stack.
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func (s *Stack) Size() int {
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return len(s.data)
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}
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