package main
import (
	"fmt"
	
)
const limit=1000000
func main(){
	var f[limit] bool
	for i:=1;i<limit; i++ {
		f[i]=true	
	}
	for i:=2;i*i<limit;i ++{
		if f[i] {
			for j:=i*i;j<limit;j+=i {
				f[j]=false
			}
		}
	}
	primes :=[]int{2,3}
	for i:=5;i<limit;i+=2 {
		if f[i] {
			primes =append(primes,i)
		}
	}
	fmt.Printf("1-100: %v\n",primes[:25])
	fmt.Printf("%d\n",len(primes))
}