random pick n person from input

apink.txt

박초롱
윤보미
정은지
손나은
김남주
오하영

randpick.go

// go run randpick.go -n3 < apink.txt

package main

import (
	"bufio"
	"flag"
	"fmt"
	"math/rand"
	"os"
	"time"
)

var flagN int

func init() {
	rand.Seed(time.Now().UnixNano())
	flag.IntVar(&flagN, "n", 1, "how many to pick")
	flag.Parse()
}

func main() {
	candidate := []string{}

	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		candidate = append(candidate, scanner.Text())
	}
	if err := scanner.Err(); err != nil {
		panic(err)
	}

	fmt.Println("candidates are", candidate)

	p := rand.Perm(len(candidate))
	for i, j := range p {
		fmt.Println("The winner is", candidate[j])
		if i+1 >= flagN {
			break
		}
	}
}