46 lines
626 B
Go
46 lines
626 B
Go
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package main
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import (
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"sync"
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)
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type Fifo struct {
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slice []string
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mu sync.Mutex
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size int
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}
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func newfifo(size int) *Fifo {
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q := Fifo{}
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q.slice = make([]string, 0)
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q.size = size
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return &q
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}
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func (q *Fifo) Add(v string) int {
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q.mu.Lock()
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i := q.Contains(v)
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if i == -1 {
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if len(q.slice) >= q.size {
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q.DeleteFirst()
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}
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q.slice = append(q.slice, v)
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}
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q.mu.Unlock()
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return i
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}
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func (q *Fifo) Contains(v string) int {
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for i, val := range q.slice {
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if val == v {
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return i
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}
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}
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return -1
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}
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func (q *Fifo) DeleteFirst() string {
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a := q.slice[0]
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q.slice = q.slice[1:]
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return a
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}
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