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; namespaceWindowsFormsApp1 { publicpartialclassForm1 : Form { publicstring s; publicdouble number1 = 0; publicdouble number2 = 0; Button btn; publicForm1() { InitializeComponent(); }