import java.util.Random;

public class test1 {
    public static void main(String[] args) {
        String str="ABCDEFGHIJKLMNOPQRSTWVUXYZabcdefghijklmnopqrstwvuxyz01234567890";
        char[] arr=str.toCharArray();   //轉為陣列
        Random r=new Random();          //建立隨機數
        for (int i = 0; i < 10; i++) {
            String code="";             //初始驗證碼，防止累計
            for (int j = 0; j < 6; j++) {
                code+=arr[r.nextInt(arr.length)];   //累加成六位驗證碼
            }
            System.out.println("隨機驗證碼:"+code);
        }
    }
}