C# Online Compiler | .NET Fiddle

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
    public static void Main()
    {
        List<Visit> visits = new List<Visit>
        {
            new Visit { VisitID = 1, PatientID = 1, DoctorID = 1, VisitDate = new DateTime(2023, 3, 10), Duration = 30 },
            new Visit { VisitID = 2, PatientID = 2, DoctorID = 2, VisitDate = new DateTime(2023, 3, 11), Duration = 60 },
            new Visit { VisitID = 3, PatientID = 3, DoctorID = 1, VisitDate = new DateTime(2023, 3, 12), Duration = 45 },
            new Visit { VisitID = 4, PatientID = 4, DoctorID = 3, VisitDate = new DateTime(2023, 3, 13), Duration = 30 },
            new Visit { VisitID = 5, PatientID = 5, DoctorID = 2, VisitDate = new DateTime(2023, 3, 14), Duration = 60 },
            // Add more visit entries as needed
        };

        List<Doctor> doctors = new List<Doctor>
        {
            new Doctor { DoctorID = 1, Name = "Dr. Smith", Specialization = "Cardiology" },
            new Doctor { DoctorID = 2, Name = "Dr. Johnson", Specialization = "Dermatology" },
            new Doctor { DoctorID = 3, Name = "Dr. Williams", Specialization = "Neurology" },
            // Add more doctor entries as needed
        };

        // Step 1: Calculate the total visit duration for each doctor
        var totalDurationPerDoctor = visits
            .GroupBy(v => v.DoctorID)
            .Select(g => new { DoctorID = g.Key, TotalDuration = g.Sum(v => v.Duration) })
            .ToList();

        // Step 2: Identify the doctor with the highest total visit duration
        var doctorWithHighestTotalDuration = totalDurationPerDoctor
            .OrderByDescending(d => d.TotalDuration)
            .First()
            .DoctorID;

        var doctorInfo = doctors.FirstOrDefault(d => d.DoctorID == doctorWithHighestTotalDuration);

        Console.WriteLine($"Doctor with Highest Total Visit Duration: {doctorInfo?.Name}, Specialization: {doctorInfo?.Specialization}");

        // Step 3: Analyze the distribution of visit durations
        var durationRanges = new[] { 0, 30, 60, 90, 120 }; // Example duration ranges in minutes
        var visitsForTopDoctor = visits.Where(v => v.DoctorID == doctorWithHighestTotalDuration).ToList();

        var durationDistribution = durationRanges
            .Zip(durationRanges.Skip(1), (min, max) => new { Min = min, Max = max })
            .Select(range => new
            {
                Range = $"{range.Min}-{range.Max} minutes",
                Count = visitsForTopDoctor.Count(v => v.Duration > range.Min && v.Duration <= range.Max)
            })
            .OrderByDescending(x => x.Count)
            .FirstOrDefault();

        Console.WriteLine($"Most Common Visit Duration Range: {durationDistribution?.Range}, Count: {durationDistribution?.Count}");
    }
}

public class Visit
{
    public int VisitID { get; set; }
    public int PatientID { get; set; }
    public int DoctorID { get; set; }
    public DateTime VisitDate { get; set; }
    public int Duration { get; set; }
}

public class Doctor
{
    public int DoctorID { get; set; }
    public string Name { get; set; }
    public string Specialization { get; set; }
}

 
using System;
using System.Collections.Generic;
using System.Linq;
​
public class Program
{
    public static void Main()
    {
        List<Visit> visits = new List<Visit>
        {
            new Visit { VisitID = 1, PatientID = 1, DoctorID = 1, VisitDate = new DateTime(2023, 3, 10), Duration = 30 },
            new Visit { VisitID = 2, PatientID = 2, DoctorID = 2, VisitDate = new DateTime(2023, 3, 11), Duration = 60 },
            new Visit { VisitID = 3, PatientID = 3, DoctorID = 1, VisitDate = new DateTime(2023, 3, 12), Duration = 45 },
            new Visit { VisitID = 4, PatientID = 4, DoctorID = 3, VisitDate = new DateTime(2023, 3, 13), Duration = 30 },
            new Visit { VisitID = 5, PatientID = 5, DoctorID = 2, VisitDate = new DateTime(2023, 3, 14), Duration = 60 },
            // Add more visit entries as needed
        };
​
        List<Doctor> doctors = new List<Doctor>
        {
            new Doctor { DoctorID = 1, Name = "Dr. Smith", Specialization = "Cardiology" },
            new Doctor { DoctorID = 2, Name = "Dr. Johnson", Specialization = "Dermatology" },
            new Doctor { DoctorID = 3, Name = "Dr. Williams", Specialization = "Neurology" },
            // Add more doctor entries as needed

True