Public Class Form1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim i, N As Integer
        Dim sum As Long = 0
        i = 1
        n = InputBox("­pºâ 1 + 2 + ... + N = ?" + vbCrLf + "½Ð¿é¤JN­È¡G")
        While i < N
            sum += i
            i += 1
        End While
        MsgBox("­pºâ1 + 2 + ... + " & N & " = " & sum)
    End Sub
End Class
