Java求助

import java.util.*;
public class Main {
    public static void main(String[] arg) {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        String b = a.substring(0,1)+a.substring(2, 5)+a.substring(6, 11);
        String c = a.substring(12, 13);
        //int n = Integer.parseInt(c);
        int[] arr = new int[9];
        int x = 0;
        for(int i=0;i<b.length();i++) {
            String d = b.substring(x, i+1);
            x++;
            arr[i] = Integer.parseInt(d);
        }
        int[] arr1 = new int[9];
        int sum = 0;
        for(int j = 0; j<arr1.length;j++) {
            arr1[j] = arr[j]*(j+1);
            sum+=arr1[j];
        }
        String e = ""+sum%11;
        if(sum%11==10) {
            e = "X";
        }
        if(c==e) {
            System.out.println("Right");
        }
        else {
            System.out.println(a.substring(0, 12)+e);
        }
    }
}