ФІО = Батарчук 2 

 Запитання:using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        int H, H_;
        int W, W_;
        bool F;
        double rez;
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_MouseDown(object sender, MouseEventArgs e)
        {
            H = e.Y;
            W = e.X;
            F = true;
            rez = 0;

        }

        private void button1_MouseUp(object sender, MouseEventArgs e)
        {
            F = false;
        }

        private void button1_MouseClick(object sender, MouseEventArgs e)
        {

            textBox1.Text = Convert.ToString(rez);
        }

        private void button1_MouseMove(object sender, MouseEventArgs e)
        {
            if (F == true)
                
            {      
                W_ = e.Y;
                H_ = e.X;
                rez = Math.Sqrt((W_ - W)*(W_ - W) + (H_ - H)*(H_ - H));
                Math.Round(rez);
                    
            }
            
            
           /* else
            {
                rez =(int) Math.Sqrt((e.X * e.X - 2 * W * e.X + W * W) + (e.Y * e.Y - 2 * H * e.Y + H * H));
                text = Convert.ToString(rez);
            }*/
               
        }

        private void textBox1_TextChanged(object sender, EventArgs e)
        {
            
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }
    }
}

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