55 lines
893 B
Go
55 lines
893 B
Go
// 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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// For more tutorials : https://learngoprogramming.com
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// In-person training : https://www.linkedin.com/in/inancgumus/
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// Follow me on twitter: https://twitter.com/inancgumus
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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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)
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func main() {
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// remember [1:] skips the first argument
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main:
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for _, arg := range os.Args[1:] {
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n, err := strconv.Atoi(arg)
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if err != nil {
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// skip non-numerics
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continue
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}
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switch {
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// prime
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case n == 2 || n == 3:
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fmt.Print(n, " ")
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continue
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// not a prime
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case n <= 1 || n%2 == 0 || n%3 == 0:
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continue
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}
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for i, w := 5, 2; i*i <= n; {
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// not a prime
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if n%i == 0 {
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continue main
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}
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i += w
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w = 6 - w
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}
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// all checks ok: it's a prime
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fmt.Print(n, " ")
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}
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fmt.Println()
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}
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