34 lines
588 B
Go
34 lines
588 B
Go
// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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// See page 96.
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// Dedup prints only one instance of each line; duplicates are removed.
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package main
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import (
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"bufio"
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"fmt"
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"os"
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)
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//!+
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func main() {
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seen := make(map[string]bool) // a set of strings
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input := bufio.NewScanner(os.Stdin)
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for input.Scan() {
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line := input.Text()
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if !seen[line] {
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seen[line] = true
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fmt.Println(line)
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}
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}
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if err := input.Err(); err != nil {
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fmt.Fprintf(os.Stderr, "dedup: %v\n", err)
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os.Exit(1)
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}
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}
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//!-
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