using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using static System.Console; //*time limit will be reached before finishing the whole program namespace Cars_LINQ_Example { delegate void Log(string s, params object[] args); class DOGGO { public static Log log = WriteLine; static void Main(string[] args) { string[] CarBrands = { "Mercedez", "Koenigsseg", "Lexus", "Toyota", "Honda", "Hyunday", "BMW", "KIA", "Chevrolet", "Tesla", "Porsche", "Lamborghini", "Ferrari", "Pagani", "Cadillac"}; log("=====YIELDING====="); IEnumerable cars = CarBrands.Where(s => s.StartsWith("T")); foreach (string car in cars) { log(car); } try { cars = CarBrands.Where(s => s[3]!='D'); foreach (string car in cars) { log(car); } } catch (IndexOutOfRangeException ex) { log("Out of range catched"); } log("=====DEFERRED QUERY====="); int[] arr = new int[] { 1, 2, 3, 4, 5 }; IEnumerable ints = arr.Select(i => i); foreach (int i in ints) { WriteLine(i); } arr[0] = 10; foreach (int i in ints) { WriteLine(i); } log("=====OPERATORS====="); log("----------WHERE"); log("--first version"); IEnumerable outCars = CarBrands.Where(s => s.StartsWith("C")); foreach (string car in outCars) { log(car); } log("--second version"); outCars = CarBrands.Where((s, i) => { return (i & 1) == 0; }); foreach (string car in outCars) { log(car); } log("----------SELECT"); log("--first version"); IEnumerable lengths = CarBrands.Select( s => s.Length); foreach (int i in lengths) { WriteLine(i); } log("--second version"); var CarsAndTheirIndexes = CarBrands.Select((s, i) => new { CarName = s, CarIndex = i}); foreach (var Car in CarsAndTheirIndexes) { log($"Car name is: {Car.CarName} Car index is: {Car.CarIndex}"); } log("----------SELECTMANY"); log("--first version"); var CarsLetters = CarBrands.SelectMany(car => { if(car.StartsWith("C"))return car.ToArray(); return new char[0];}); foreach (char c in CarsLetters) { WriteLine(c); } log("--second version"); CarsLetters = CarBrands.SelectMany((car,index) => { if((index&1) == 0)return car.ToArray(); return new char[0]; }); foreach (char c in CarsLetters) { Write(c); } log("\n----------TAKE"); IEnumerable ThreeCars = CarBrands.Take(3); foreach (string car in ThreeCars) { log(car); } log("\n----------TAKEWHILE"); log("--first version"); cars = CarBrands.TakeWhile(s => s.Length > 3); foreach (string car in cars) { log(car); } log("--second version"); cars = CarBrands.TakeWhile((s,i) => i < 5); foreach (string car in cars) { log(car); } log("\n----------SKIP"); IEnumerable CarsWithoutFirstThree = CarBrands.Skip(3); foreach (string car in CarsWithoutFirstThree) { log(car); } log("\n----------SKIPWHILE"); log("--first version"); cars = CarBrands.SkipWhile(s => !s.StartsWith("C")); foreach (string car in cars) { log(car); } log("--second version"); cars = CarBrands.SkipWhile((s, i) => i < 5); foreach (string car in cars) { log(car); } log("\n----------CONCAT"); string[] FewMoreCars = { "Acura", "Nissan" }; cars = CarBrands.Concat(FewMoreCars); foreach (string car in cars) { log(car); } log("\n----------ORDERBY"); log("--first version"); cars = CarBrands.OrderBy(s => s.Length); foreach (string car in cars) { log(car); } log("--second version"); MyStringComparer comparer = new MyStringComparer(); cars = CarBrands.OrderBy((s => s), comparer); foreach (string car in cars) { log(car); } log("\n----------ORDERBYDESCENDING"); log("--first version"); cars = CarBrands.OrderByDescending(s => s.Length); foreach (string car in cars) { log(car); } log("--second version"); cars = CarBrands.OrderByDescending((s => s), comparer); foreach (string car in cars) { log(car); } log("\n----------THENBY"); log("--first version"); cars = CarBrands.OrderBy(s => s.Length).ThenBy(s => s); foreach (string car in cars) { log(car); } log("--second version"); comparer = new MyStringComparer(); cars = CarBrands.OrderBy(s => s.Length).ThenBy(s=>s, comparer); foreach (string car in cars) { log(car); } log("\n----------THENBYDESCENDING"); log("--first version"); cars = CarBrands.OrderBy(s => s.Length).ThenByDescending(s => s); foreach (string car in cars) { log(car); } log("--second version"); comparer = new MyStringComparer(); cars = CarBrands.OrderBy(s => s.Length).ThenByDescending(s => s, comparer); foreach (string car in cars) { log(car); } log("\n----------REVERSE"); cars = CarBrands.Reverse(); foreach (string car in cars) { log(car); } log("\n----------JOIN"); int[] Lenghts = { 3, 4, 5, 6, 7, 8, 9 }; var outStructs = CarBrands.Join(Lenghts, s => s.Length, l => l, (s, l) => new { name = s, length = l }); foreach (var Car in outStructs) { log($"Car name is: {Car.name} Car name length is: {Car.length}"); } log("\n----------GROUPJOIN"); int[] Len = { 3, 4, 5, 6, 7, 8, 9 }; var outValues = CarBrands.GroupJoin(Len, s => s.Length > 5, l => l > 5, (s, lens) => new { name = s, lensplus = lens }); foreach (var car in outValues) { log($"Car name is: {car.name} name length: {car.name.Length} Lengths bigger or smaller and equal than 5: "); foreach (int l in car.lensplus) { WriteLine(l); } } log("\n----------GROUPBY"); log("--first version"); IEnumerable> grouppedCars = CarBrands.GroupBy(s => s.Length); foreach(IGrouping element in grouppedCars) { log($"Length: {element.Key} Names:"); foreach(string s in element) { log(s); } } log("--second version"); IntComparer comp = new IntComparer(); grouppedCars = CarBrands.GroupBy(s => s.Length,comp); foreach (IGrouping element in grouppedCars) { log($"Length: {element.Key} Names:"); foreach (string s in element) { log(s); } } log("--third version"); IEnumerable> grouppedLengths = CarBrands.GroupBy(s => s.Length, el => el.Length); foreach (IGrouping element in grouppedLengths) { log($"Length group: {element.Key} Cars lengths:"); foreach (int s in element) { WriteLine(s); } } log("--fourth version"); grouppedLengths = CarBrands.GroupBy(s => s.Length, el => el.Length, comp); foreach (IGrouping element in grouppedLengths) { log($"Length group: {element.Key} Cars lengths:"); foreach (int s in element) { WriteLine(s); } } log("\n----------DISTINCT"); string[] names = { "Sergey", "Sergey", "John", "James", "John", "Mary", "Alexander" }; IEnumerable dist = names.Distinct(); foreach (string s in dist) { log(s); } log("\n----------UNION"); string[] names2 = { "Mary", "Alexander", "James", "Richard", "Julia" }; IEnumerable uniqueNames = names.Union(names2); foreach (string s in uniqueNames) { log(s); } log("\n----------INTERSECT"); IEnumerable intersNames = names.Intersect(names2); foreach (string s in intersNames) { log(s); } log("\n----------EXCEPT"); IEnumerable exceptNames = names.Except(names2); foreach (string s in exceptNames) { log(s); } log("\n----------CAST"); int[] integers = { 1, 2, 3, 4, 5, 6, 7 }; IEnumerable

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