static void Main(string[] args)
{
var random = new Random();
var months = new[] { "January", "February", "March", "April",
"May", "June", "July", "August", "September", "October", "November", "December" }.OrderBy(el => random.Next()).ToArray();
//1.1
var n = 7;
var monthQuery = months.Where(month => month.Length == n);
foreach (var month in monthQuery)
{
Console.WriteLine(month);
}
//1.2
Predicate <int> isWinterMonth = number => number == 1 || number == 2 || number == 12;
Predicate <int> isSummerMonth = number => number == 6 || number == 7 || number == 8;
var seasonQuery = from month in months
let monthNumber = Array.IndexOf(CultureInfo.InvariantCulture.DateTimeFormat.MonthNames, month) + 1
where isWinterMonth(monthNumber) || isSummerMonth(monthNumber)
select month;
foreach (var month in seasonQuery)
{
Console.WriteLine(month);
}
//1.3
var monthUQuery = months.Where(month => month.Length >= 4 && month.Contains('u'));
foreach (var month in monthUQuery)
{
Console.WriteLine(month);
}
//2
var students = new[]
{
new Student("тумаш станислав игоревич 22.08.2001", "улица блаблабла", "+375255377984", "ФИТ", 2, 1),
new Student("савельев талан михайлович 03.07.1998", "улица1 блаблабла", "+375445938865", "ХТиТ", 2, 3),
new Student("стельмаков константин ЕВГЕНЬЕВИЧ 14.06.2001", "улица2 блаблабла", "+375335785843", "ФИТ", 2, 4),
new Student("василевич владимир павлович 21.03.2000", "улица3 блаблабла", "+375255377994", "ФИТ", 2, 3),
new Student("удовыдченкова анастасия александровна 12.01.2001", "улица4 блаблабла", "+375334845667", "ФИТ", 2, 9),
new Student("карпенкин дмитрий анатольевич 28.04.1999", "улица5 блаблабла", "+375257359612", "ФИТ", 2, 4),
new Student("дежемесов александр егорович 29.12.2001", "улица6 блаблабла", "+375335785968", "ФИТ", 2, 3),
new Student("челик какой-то нормальный 9.11.1996", "улица7 блаблабла", "+375335785968", "ФИТ", 2, 3),
new Student("пулатов александр егорович 29.12.2001", "улица8 блаблабла", "+375335987777", "ФИТ", 2, 2),
new Student("пулатов михаил егорович 29.12.2001", "улица9 блаблабла", "+375335537769", "ФИТ", 1, 3),
new Student("липенко дмитрий павлович 220.10.2000", "улица10 блаблабла", "+375257359612", "ХТиТ", 2, 4),
};
//3.1
var faculty = "фит";
var studentFacultyQuery = students
.Where(student => string.Equals(student.Faculty, faculty, StringComparison.OrdinalIgnoreCase))
.OrderBy(student => student.FullName.First());
foreach (var student in studentFacultyQuery)
{
Console.WriteLine(student);
}
//3.2
var group = 3;
var studentGroupFacultyQuery = students
.Where(student => string.Equals(student.Faculty, faculty, StringComparison.OrdinalIgnoreCase) && student.Group == group);
foreach (var student in studentGroupFacultyQuery)
{
Console.WriteLine(student);
}
//3.3
var youngestStudent = students.Min();
Console.WriteLine(youngestStudent);
//3.4
var studentGroupQuery = students
.Where(student => student.Group == group)
.OrderBy(student => student.Surname.First());
foreach (var student in studentGroupQuery)
{
Console.WriteLine(student);
}
//3.5
var name = "дмитрий";
var firstWithName = students.First(student => string.Equals(student.Name, name, StringComparison.OrdinalIgnoreCase));
Console.WriteLine(firstWithName);
//4-5
//минимальный возраст в каждой группе 2 курса по убыванию возраста
var groupAge =
from GA in
from student in students
where student.Course == 2
group student by student.Group into SG
select new
{
Group = SG.Key,
Age = SG.Min(student => student.Age)
}
orderby GA.Age descending
select GA;
//является ли в хотя бы 1 группе 19 минимальным возрастом
bool isAny = groupAge.Any(GA => GA.Age == 17);
//пары студент минимальный возраст в его группе
var studentGroupAge = (from student in students
join GA in groupAge on student.Group equals GA.Group
select new
{
Student = student,
GA.Age
}).Skip(2); //Skip чтоб было
}