C#洗牌演算法

protected void Button1_Click(object sender, EventArgs e)
    {
        string[] qian = new string[52]{"Ahe", "2he", "3he", "4he", "5he", "6he", "7he", "8he", "9he", "10he", "Jhe", "Qhe", "Khe",
            "Ah","2h","3h","4h","5h","6h","7h","8h","9h","10h","Jh","Qh","Kh","Am", "2m", "3m", "4m", "5m", "6m", "7m", "8m", "9m", "10m", "Jm", "Qm", "Km",
            "Af", "2f", "3f", "4f", "5f", "6f", "7f", "8f", "9f", "10f", "Jf", "Qf", "Kf"};
        Response.Write("洗牌前"+"<br>");
        foreach (string s1 in qian)
        {
            Response.Write(s1 + " ");
        }
        System.Random r1 = new Random();
       // System.Random r2 = new Random();
        for (int j = 0; j < 5200; j++)
        {
            int a = Convert.ToInt32(r1.Next(0, 51));
            int b = Convert.ToInt32(r1.Next(0, 51));
            string t = string.Empty;
                t = qian[a];
                qian[a] = qian[b];
                qian[b] = t;
        }
        Response.Write("<br>"+"洗牌後：" + "<br>");
        foreach (string s in qian)
        {
          
            Response.Write(s + " ");
        }
    }