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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form2 : Form
    {
        int n;
        Random ran;
        public Form2()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            button1.Visible = false;
            label1.Visible = true;
            button2.Visible = true;
            button3.Visible = true;
            label2.Visible = true;
            pictureBox1.Image = Image.FromFile("p5.gif");
            n = ran.Next(2,100);
            label2.Text = Convert.ToString(n);
        }

        private void button2_Click(object sender, EventArgs e)
        {
            label1.Visibl = false;
            button2.Visible = false;
            button3.Visible = false;
            label2.Visible = true;
            button1.Visible = true;
            if (prim(n))
            {
                pictureBox1.Image = Image.FormFile("p4.gif");
            }
            else
                pictureBox1.Image = Image.FormFile("p6.gif");
        }
    }
}