using System;

public class Program

{

    public static void Main()

    {

    // Get user information (professor)

        Console.WriteLine("Please enter nummber of professors.");

        string strProfessor = Console.ReadLine();

        int iProfessor;

        bool isValid1 = Int32.TryParse(strProfessor, out iProfessor);

    // Validity Rules (Professor)

        if (isValid1 == false)

        {

            Console.WriteLine("Please enter a valid whole number.");

            return;

        }

        else if (iProfessor <1)

        {

            Console.WriteLine("Please enter a valid number greater than zero.");

            return;

        }

        // Get user information (Staff)

        Console.WriteLine("Please enter number of staff.");

        string strStaff = Console.ReadLine();

        int iStaff;

        bool isValid2 = Int32.TryParse(strStaff, out iStaff);

        // Validity rule (Staff)

        if (isValid2 == false)

        {

            Console.WriteLine("Please enter a valid whole number.");

            return;

        }

        else if (iProfessor <1)

        {

            Console.WriteLine("Please enter a valid number greater than zero.");

            return;

        }

        // Get user information (Student)

        Console.WriteLine("Please enter number of students.");

        string strStudent = Console.ReadLine();

        int iStudent;

        bool isValid3 = Int32.TryParse(strStudent, out iStudent);

        // Validity rule (Student)

        if (isValid3 == false)

        {

            Console.WriteLine("Please enter a valid whole number.");

            return;

        }

        else if (iProfessor <1)

        {

            Console.WriteLine("Please enter a valid number greater than zero.");

            return;

        }

    // Calculate # of respective items 

    double dMasks = Math.Ceiling((5.5 * iProfessor) + (3.5 * iStaff) + (4.5 * iStudent));

    double dHS = Math.Ceiling((1.2 * iProfessor) + (0.8 * iStaff) + (2.1 * iStudent));

    double dGlove = Math.Ceiling(3.5 * iProfessor) + (2.8 * iStaff) + (2.5 * iStudent);

    Console.WriteLine("-------------------------");

    Console.WriteLine("-------------------------");

    // Display number of respective items   

    Console.WriteLine("# Masks: " + dMasks);

    Console.WriteLine("# Hand Sanatizers: " + dHS);

    Console.WriteLine("# Gloves: " + dGlove);

    int iSavingP = 100;

    int iSavingStaff = 80;

    int iSavingStudent = 150;

    double dMaskCost = 8.5;

    double dHandCost = 15.5;

    double dGlovesCost = 6.5;

    double dSavings = (iSavingP * iProfessor + iSavingStaff * iStaff + iSavingStudent * iStudent) - (dMaskCost * dMasks + dHandCost * dHS + dGlovesCost * dGlove) - 250;

    Console.WriteLine("Benefits: $" + dSavings);

    }

}

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