go求质数

go求质数

package main

import (
    "fmt"
    "flag"
    )

var num int
func init() {
    flag.IntVar(&num, "num", 100, "The greeting object.")
}

func main() {
    flag.Parse()
    if(num <= 0){
        fmt.Printf("%v \n", "参数必须大于0")
        return
    }
    prime := []int{1}
    for a := 2; a <= num; a++ {
        for k := range prime {
            v := prime[k]
            if(a % v == 0 && v != 1){
                goto Loop
            }
        }
        prime = append(prime, a)
        Loop:
    }
    fmt.Printf("%v \n", prime)
}