PRACTICA 5.2 C

class Program
{
static void Main(string[] args)
{
int cl;
do
{
Console.WriteLine("introduce calificacion");
cl = int.Parse(Console.ReadLine());
Console.WriteLine("la calificacion:{0}", cl);
if (cl <> 100)
Console.WriteLine("calificacion incorrecta");
}
while (cl != 999);
Console.Read();

PRACTICA EN WINDOWS

namespace practica_5._5_windows
{
public partial class Form1 : Form
{
int c1, codigo = 999;
public Form1()
{
c1 = 0;
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
c1 = int.Parse(textBox1.Text);
if (c1 == codigo)
Close();
if (c1 <> 100)
{
textBox1.Enabled = false;
listBox1.Items.Add("Calificacion Incorrecta");
}
else
{
listBox1.Items.Add(c1);
}
}
private void button2_Click(object sender, EventArgs e)
{
textBox1.Enabled = true;
textBox1.Clear();
listBox1.Items.Clear();
}
private void button3_Click(object sender, EventArgs e)
{
Close();