关于条形码的一个简单小程序-欢迎鉴赏-批评

源代码：
import java.util.Scanner;
public class BarCodeDemo {
public static void main(String[] args) {
Scanner console = new Scanner(System.in);
System.out.println("请输入条形码");
String a =console.nextLine();
int i=1,sum1=0,sum2=0,sum=0;
for(;i<=11;i+=2){
sum1+=a.charAt(i)-'0';
}
sum1=sum1*3;
for(i=2;i<=11;i+=2){
sum2+=a.charAt(i)-'0';
}
sum=sum1+sum2;
int d=(sum/10+1)*10;
if(sum%10==0)d=sum;
int code=d-sum;
if(a.charAt(0)-'0'==code){
System.out.println("条形码正确");
}else{
System.out.println("请重新扫描");
}
}
}