using System;
using System.Collections.Generic;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using System.Linq;

namespace TestAnnTask
{
    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void SimpleTest()
        {
            var n = 10;
            var listBig = new List<List<int>>()
            {
                new List<int> {5, 7, 8, 9 },
                new List<int> {8, 9, 10, 12},
                new List<int> {2, 7, 7, 8, 9},
            };
            var expectedResult = listBig
                                        .SelectMany(t => t)
                                        .OrderBy(t => t)
                                        .Take(n);
           CollectionAssert.AreEqual(expectedResult, );
        }

        [TestMethod]
        public void HardTest()
        {
            var n = 7;
            var listBig = new List<List<int>>()
            {
                Enumerable.Range(100, 500).ToList(),
                Enumerable.Range(1, 1000).ToList(),
                Enumerable.Range(50, 160).ToList(),
                Enumerable.Range(70, 1000).ToList(),
                Enumerable.Range(1000, 2000).ToList(),
                Enumerable.Range(1000, 4000).ToList(),
            };
            var expectedResult = listBig
                                        .SelectMany(t => t)
                                        .OrderBy(t => t)
                                        .Take(n);
            CollectionAssert.AreEqual(expectedResult, );
        }

        [TestMethod]
        public void EmptyList()
        {
            var n = 7;
            var listBig = new List<List<int>>()
            {
                new List<int>() { },
                new List<int>() {1, 7, 8},
            };
            var expectedResult = listBig
                                        .SelectMany(t => t)
                                        .OrderBy(t => t)
                                        .Take(n);
            CollectionAssert.AreEqual(expectedResult, );
        }

        [TestMethod]
        public void TestOneElementInList()
        {
            var n = 3;
            var listBig = new List<List<int>>()
            {
                new List<int>() {1},
                new List<int>() {2},
                new List<int>() {7},
                new List<int>() {18},
            };
            var expectedResult = listBig
                                        .SelectMany(t => t)
                                        .OrderBy(t => t)
                                        .Take(n);
            CollectionAssert.AreEqual(expectedResult, );
        }
    }
}