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using System;
using System.Windows.Forms;

namespace _17_april
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text.Length == 0 || textBox2.Text.Length == 0)
            {
                MessageBox.Show("Введите требуемые значения!", "Ошибка!", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            else
            {
                double x = double.Parse(textBox1.Text.Replace(".", ","));
                double epsilon = double.Parse(textBox2.Text.Replace(".", ","));

                listBox1.Items.Clear();
                double term;
                int iteration = 1;

                do
                {
                    term = Math.Pow(x, iteration) / Factorial(iteration) * Math.Pow(-1, iteration - 1);
                    if (Math.Abs(term) > epsilon)
                    {
                        listBox1.Items.Add($"{iteration,-10} {x,-20:F10} {term,-20:F10}");
                    }
                    iteration++;
                } while (Math.Abs(term) > epsilon);

                textBox3.Text = (iteration - 1).ToString();
                textBox4.Text = term.ToString("F10");
            }
        }

        private double Factorial(int n)
        {
            if (n == 0) return 1;
            double result = 1;
            for (int i = 1; i <= n; i++)
            {
                result *= i;
            }
            return result;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
    }
}