37 lines
606 B
Go
37 lines
606 B
Go
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package discoverychain
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type stringStack []string
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func (s stringStack) Len() int {
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return len(s)
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}
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func (s *stringStack) Push(v string) {
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*s = append(*s, v)
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}
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func (s *stringStack) Pop() (string, bool) {
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if len(*s) == 0 {
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return "", false
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}
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size := len(*s)
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v := (*s)[size-1]
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*s = (*s)[0 : size-1]
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return v, true
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}
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func (s stringStack) Peek() (string, bool) {
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if len(s) == 0 {
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return "", false
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}
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return s[len(s)-1], true
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}
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// Items returns the underlying slice. The first thing Pushed onto the stack is
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// in the 0th slice position.
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func (s stringStack) Items() []string {
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return s
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}
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