Imports System
Public Class WeekdayCalculatorBetweenTwoDates
Public Shared Sub Main()
Console.WriteLine(countWeekDays(New DateTime(2025, 1, 1), New DateTime(2025, 1, 7)))
Console.WriteLine(countWeekDays(New DateTime(2025, 2, 1), New DateTime(2025, 2, 10)))
Console.WriteLine(countWeekDays(New DateTime(2024, 1, 1), New DateTime(2024, 12, 31)))
Console.WriteLine(countWeekDays(New DateTime(2025, 1, 1), New DateTime(2025, 12, 31)))
End Sub
Public Shared Function countWeekDays(ByVal d1 As DateTime, ByVal d2 As DateTime) As Integer
Dim ndays As Integer = 1 + Convert.ToInt32((d2 - d1).TotalDays)
Dim nsaturdays As Integer = (ndays + Convert.ToInt32(d1.DayOfWeek)) / 7
Return ndays - 2 * nsaturdays - (If(d1.DayOfWeek = DayOfWeek.Sunday, 1, 0)) + (If(d2.DayOfWeek = DayOfWeek.Saturday, 1, 0))
End Function
End Class
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