////

using System;
using System.Drawing;
using System.Windows.Forms;

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnHesapla_Click(object sender, EventArgs e)
        {
            if (TryGetGrades(out double y1, out double y2, out double p1, out double p2))
            {
                double ort = CalculateAverage(y1, y2, p1, p2);
                DisplayResult(ort);
            }
            else
            {
                lblOrtalama.Text = "Hatalı giriş.";
                lblDurum.Text = "Hatalı giriş.";
                lblDurum.ForeColor = Color.Black;
            }
        }

        private bool TryGetGrades(out double y1, out double y2, out double p1, out double p2)
        {
            return double.TryParse(txtYazili1.Text, out y1) &&
                   double.TryParse(txtYazili2.Text, out y2) &&
                   double.TryParse(txtPerformans1.Text, out p1) &&
                   double.TryParse(txtPerformans2.Text, out p2);
        }

        private double CalculateAverage(double y1, double y2, double p1, double p2)
        {
            return (y1 + y2 + p1 + p2) / 4;
        }

        private void DisplayResult(double ort)
        {
            lblOrtalama.Text = ort.ToString();
            if (ort >= 50)
            {
                lblDurum.Text = "GEÇTİNİZ";
                lblDurum.ForeColor = Color.Green;
            }
            else
            {
                lblDurum.Text = "KALDINIZ";
                lblDurum.ForeColor = Color.Red;
            }
        }
    }
}