把字符串转成char[] 除了我还能有谁 (效率down down)

import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        char[] str = scan.nextLine().toCharArray();
        int j,k;
        for(int i = 0; i<str.length;i+=8){
            for(j = i;j - i < 8 && j<str.length;j++){
                System.out.print(str[j]);
            }
            for(k = 8 - j%8;k>0&&j%8!=0;k--){
                System.out.print("0");
            }
            System.out.println();
        }
    }
}