71 lines
1.4 KiB
Go
71 lines
1.4 KiB
Go
package main
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import (
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"fmt"
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"io/ioutil"
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"os"
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"sort"
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)
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// ---------------------------------------------------------
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// EXERCISE: Sort and write items to a file with their ordinals
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//
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// Use the previous exercise.
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//
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// This time, print the sorted items with ordinals
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// (see the expected output)
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//
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//
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// EXPECTED OUTPUT
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//
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// go run main.go
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// Send me some items and I will sort them
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//
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// go run main.go orange banana apple
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//
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// cat sorted.txt
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// 1. apple
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// 2. banana
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// 3. orange
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//
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//
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// HINTS
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//
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// ONLY READ THIS IF YOU GET STUCK
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//
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// + You can use strconv.AppendInt function to append an int
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// to a byte slice. strconv contains a lot of functions for appending
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// other basic types to []byte slices as well.
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//
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// + You can append individual characters to a byte slice using
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// rune literals (because: rune literal are typeless numerics):
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//
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// var slice []byte
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// slice = append(slice, 'h', 'i', ' ', '!')
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// fmt.Printf("%s\n", slice)
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//
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// Above code prints: hi !
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// ---------------------------------------------------------
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func main() {
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items := os.Args[1:]
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if len(items) == 0 {
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fmt.Println("Send me some items and I will sort them")
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return
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}
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sort.Strings(items)
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var data []byte
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for _, s := range items {
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data = append(data, s...)
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data = append(data, '\n')
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}
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err := ioutil.WriteFile("sorted.txt", data, 0644)
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if err != nil {
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fmt.Println(err)
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return
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}
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}
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