Simple Calculator(scan and print)

import java.util.Scanner;

class apples{
    public static void main(String args[]){
        Scanner scan = new Scanner(System.in);
        double fnum, snum, ans;
        System.out.println("Please enter first num: ");
        fnum = scan.nextDouble();
        System.out.println("Please enter second num: ");
        snum = scan.nextDouble();
        ans = fnum + snum;
        Systen.out.println(ans);

    }
}