Module AAAAAAAA
    Sub Main(ByVal args() As String)
        Dim n As Integer = Console.ReadLine()
        Dim h As Integer = Console.ReadLine()
        Dim w As Integer = Console.ReadLine()
        dim ans as integer = 0 
      
    for x　as integer =1 to n
    for y as integer =1 to n
    if x+w-1 <= n then
            if y+h-1 <= n then
                ans +=1
            end if
        end if
      next
      next

    Console.WriteLine(ans)

    End Sub
End Module