import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Random;
import java.util.Scanner;


public class demo {
    static int MAX = 100;
    static char[] key = new char[MAX];                            //用于保存密钥
    static int len;

    static char[] bitcode(char[] str)                    //一次一密加密算法
    {
        int i;
        char[] wen;

        if ((wen = new char[len + 1]) == null) {
            System.out.printf("申请内存失败!\n");
            System.exit(1);
        }
        for (i = 0; i < len; i++) {
            wen[i] = (char) (str[i] ^ key[i]);                //异或运算
        }
        wen[len] = '\0';
        return wen;
    }

    public static void main(String[] args) throws IOException {
        int i;
        char[] srcstr = new char[MAX];
        char[] miwen, mingwen;
        String go;
        Scanner input = new Scanner(System.in);
//        srand(time(NULL));                    //随机种子
        System.out.printf("一次一密加密解密算法演示！\n");

        do {
            System.out.printf("请输入明文字符串：");

            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
            String str = bufferedReader.readLine();

            srcstr = str.toCharArray();
            //明文信息
            Random r = new Random();                    //随机种子
            len = srcstr.length;
            for (i = 0; i < len; i++) {
                key[i] = (char) (r.nextInt(10) + '0');            //产生密钥序列
            }
            System.out.printf("此次加密解密演示的密钥序列为：");
            for (i = 0; i < len; i++) {
                System.out.printf("%c", key[i]);
            }
//        System.out.printf("\n");
            miwen = bitcode(srcstr);                //加密
            System.out.printf("\n输入的明文为：");
            for (i = 0; i < srcstr.length; i++)
                System.out.print(srcstr[i]);
            System.out.printf("\n加密后的密文为：");
            for (i = 0; i < miwen.length; i++)
                System.out.print(miwen[i]);
            mingwen = bitcode(miwen);                //解密
            System.out.printf("\n解密出的明文为：");
            for (i = 0; i < mingwen.length; i++)
                System.out.print(mingwen[i]);

            System.out.print("\n\n继续执行(y/n)?");

            go = input.next();
        } while (go.equalsIgnoreCase("y"));
        System.out.println("演示结束！");

    }

}