53 lines
1000 B
Go
53 lines
1000 B
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import (
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"fmt"
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"os"
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"strconv"
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"strings"
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)
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// ---------------------------------------------------------
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// CHALLENGE
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// Add error handling to the feet to meters program.
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//
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// EXPECTED OUTPUT
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// go run main.go hello
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// error: 'hello' is not a number.
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//
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// go run main.go what
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// error: 'what' is not a number.
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//
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// go run main.go 100
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// 100 feet is 30.48 meters.
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// ---------------------------------------------------------
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const usage = `
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Feet to Meters
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--------------
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This program converts feet into meters.
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Usage:
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feet [feetsToConvert]`
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func main() {
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if len(os.Args) < 2 {
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fmt.Println(strings.TrimSpace(usage))
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return
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}
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arg := os.Args[1]
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feet, _ := strconv.ParseFloat(arg, 64)
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meters := feet * 0.3048
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fmt.Printf("%g feet is %g meters.\n", feet, meters)
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}
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