2. félév 11. hét

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    internal class Program
    {
        private static Random random = new Random();
        static void Main(string[] args)
        {
            List<Person> people = new List<Person>();
            for (int i = 0; i < 10; ++i)
            {
                people.Add(new Person($"Person{i}", (i + 1) * 10, random.Next(200, 1501)));
            }
            //people[4] = people[0];

            bool azE = HalmazE(people);
            Console.WriteLine(azE);

            bool tartE = TartalmazE(people, people[0]);
            Console.WriteLine(tartE);

            bool tartENemxD = TartalmazE(people, new Person("xy", 1, 1));
            Console.WriteLine(tartENemxD);

            bool reszE = ReszhalmazE(people, new List<Person>() { people[0], people[1], people[2] });
            Console.WriteLine(reszE);

            Console.Read();
        }

        private static bool HalmazE(List<Person> people)
        {
            int i = 1;
            while (i < people.Count && people[i] != people[i-1])
            {
                ++i;
            }

            return i == people.Count;
        }

        private static bool TartalmazE(List<Person> people, Person person)
        {
            int bal = 0;
            int jobb = people.Count-1;
            int center = (bal+jobb) / 2;

            while (bal <= jobb && people[center].CompareTo(person) != 0)
            {
                if (people[center].CompareTo(person) == -1)
                {
                    jobb = center - 1;
                }
                else
                {
                    bal = center + 1;
                }
                center = (bal+jobb) / 2;
            }
            return bal <= jobb;
        }

        private static bool ReszhalmazE(List<Person> people, List<Person> people2)
        {
            int j = 0;
            int i = 0;
            while (i < people.Count && j < people2.Count && people[i].Age >= people2[i].Age)
            {
                if (people[i] == people2[i])
                {
                    ++i;
                }
                ++j;
            }

            return i >= j;
        }
    }
}

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    internal class Person : IComparable
    {
        private int age;
        private int salary;
        private string name;

        public Person(string name, int age, int salary)
        {
            this.name = name;
            this.age = age;
            this.salary = salary;
        }

        public string Name { get => this.name; set => this.name = value; }
        public int Age { get => this.age; set => this.age = value; }
        public int Salary { get => this.salary; set => this.salary = value; }

        public int CompareTo(object obj)
        {
            if (obj == null)
            {
                Person p = obj as Person;

                if (p.age > this.age) return 1;
                if (p.age < this.age) return -1;
            }

            return 0;
        }
    }
}