static void Main(string[] args)
{
var numbers = new int[] { 5, 10, 17, 9, 3, 21, 10, 40, 21, 3, 35 };
var books = Books.GetBooks();
#region 問題6-1
//問題6-1-1
//Console.WriteLine("問題6-1-1");
//Console.WriteLine(numbers.Max());
//問題6-1-2
//Console.WriteLine("問題6-1-2");
//int pos = numbers.Length - 2;
//numbers.Skip(pos).ToList().ForEach(f => Console.Write(f + " "));
//問題6-1-3
//Console.WriteLine();
//Console.WriteLine("問題6-1-3");
//numbers.Select(s => s.ToString()).ToList().ForEach(f => Console.Write(f + " "));
//問題6-1-4
//Console.WriteLine();
//Console.WriteLine("問題6-1-4");
//numbers.OrderBy(o => o).Take(3).ToList().ForEach(f => Console.Write(f + " "));
//問題6-1-5
//Console.WriteLine();
//Console.WriteLine("問題6-1-5");
//Console.WriteLine(numbers.Distinct().Count(c => c > 10));
#endregion
#region 問題6-2
//問題6-2-1
Console.WriteLine("問題6-2-1");
var book = books.Where(f => f.Title == "ワンダフル・C#ライフ");
//var book = books.FirstOrDefault(f => f.Title == "ワンダフル・C#ライフ");
foreach (var item in book)
{
Console.WriteLine($"価格:{item.Price} ページ数:{item.Pages}");
}
//問題6-2-2
Console.WriteLine("問題6-2-2");
var selected = books.Count(c => c.Title.Contains("C#"));
Console.WriteLine($"{selected}冊");
//問題6-2-3
Console.WriteLine("問題6-2-3");
var sa = books.Where(c => c.Title.Contains("C#")).Average(a => a.Pages);
Console.WriteLine(sa);
//問題6-2-4
Console.WriteLine("問題6-2-4");
var bookp = books.Where(w => w.Price >= 4000);
foreach (var bookps in bookp)
{
Console.WriteLine(bookps.Title);
}
//問題6-2-5
Console.WriteLine("問題6-2-5");
var pt = books.Where(w => w.Price < 4000).Max(m => m.Pages);
Console.WriteLine(pt);
//問題6-2-6
Console.WriteLine("問題6-2-6");
var bookpt = books.Where(w => w.Pages >= 400).OrderByDescending(o => o.Price);
foreach (var bookpts in bookpt)
{
Console.WriteLine($"{bookpts.Title} {bookpts.Price}");
}
//問題6-2-7
Console.WriteLine("問題6-2-7");
var bookppt = books.Where(w => w.Title.Contains("C#") && w.Pages <= 500);
foreach (var bookppts in bookppt)
{
Console.WriteLine(bookppts.Title);
}
#endregion
//すべての書籍から、「C#」の文字がいくつあるかをカウントする
//int count = 0;
//foreach (var book in books.Where(b => b.Title.Contains("C#")))
//{
// for (int i = 0; i < book.Title.Length-1; i++)
// {
// if ((book.Title[i] == 'C')&&(book.Title[i+1]=='#'))
// {
// count++;
// }
// }
//}
//Console.WriteLine($"文字列「C#」の個数は{count}です。");
}
static void Main(string[] args)
{
#region P.163まで
//var numbers = Enumerable.Range(1, 20).ToArray();
//foreach (var item in numbers)
//{
// Console.WriteLine(item);
//}
#endregion
#region P.175
//var numbers = new List<int> { 9, 7, -5, 4, 2, 5, 4, 2, -4, 8, -1, 6, 4, };
//Console.WriteLine($"平均値：{numbers.Average()}");
//Console.WriteLine($"合計値：{numbers.Sum()}");
//Console.WriteLine($"最小値：{numbers.Where(n => n > 0).Min()}");
//Console.WriteLine($"最大値：{numbers.Min()}");
////7の倍数があるのか
//bool exists = numbers.Any(n => n % 7 == 0);
//var results = numbers.Where(n => n > 0).Take(3);
//foreach (var result in results)
//{
// Console.Write(result + " ");
//}
//Console.WriteLine("\n-----------------------------");
//var books = Books.GetBooks();
//Console.WriteLine($"本の平均価格：{books.Average(x => x.Price)}");
//Console.WriteLine($"本の合計価格：{books.Sum(x => x.Price)}");
//Console.WriteLine($"本のページが最大：{books.Max(x => x.Pages)}");
//Console.WriteLine($"高価な本：{books.Max(x => x.Price)}");
//Console.WriteLine($"タイトルに「物語」がある冊数：{books.Count(x => x.Title.Contains("物語"))}");
////600ページを超える書籍があるか？(Anyメソッド)
////if (books.Any(n => n.Pages > 600))
////{
//// Console.WriteLine("存在する");
////}
//Console.Write("600ページを超える書籍は");
//Console.WriteLine(books.Any(x => x.Pages > 600) ? "ある" : "ない");
////すべてが200ページ以上の書籍化？(Allメソッド)
////if (books.All(n=>n.Pages>=200))
////{
//// Console.WriteLine("すべて200ページ以上です");
////}
//Console.WriteLine();//改行
//Console.Write("600ページを超える書籍は");
//Console.WriteLine(books.All(x => x.Pages >= 200) ? "あります" : "ありません");
////400ページを超える本は何冊か？(FirstOrDefaultメソッド)
//Console.WriteLine();//改行
////var book = books.FirstOrDefault(x => x.Pages > 400);
////int i;
////for (i = 0; i < books.Count; i++)
////{
//// if (books[i].Title.Contains(book.Title))
//// {
//// break;
//// }
////}
//var count = books.FindIndex(x => x.Pages > 400);
////Console.WriteLine($"400ページを超える本は{i + 1}冊目です");
//Console.WriteLine($"400ページを超える本は{count + 1}冊目です");
////本の値段が400円以上のものを3冊表示
//Console.WriteLine();//改行
//Console.WriteLine("本の値段が400円以上は");
//var rt = books.Where(n => n.Price >= 400).Take(3);
//foreach (var item in rt)
//{
// Console.WriteLine(item.Title);
//}
#endregion
//整数の例
var numbers = new List <int>
{
19, 17, 15, 24, 12, 25, 14, 20, 12, 28, 19, 30, 24
};
//var strings = numbers.Select(n => n.ToString("0000")).ToArray();
var strings = numbers.Distinct().ToArray();
foreach (var str in strings)
{
Console.Write(str + " ");
}
numbers.Select(n => n.ToString("0000")).ToList().ForEach(s => Console.Write(s + " "));
//並べ替え
Console.WriteLine();
var sortedNumbers = numbers.OrderBy(n => n);
foreach (var nums in sortedNumbers)
{
Console.WriteLine(nums + " ");
}
//文字列の例
Console.WriteLine("\n\n-----------------------");
var words = new List <string>
{
"Microsoft", "Apple", "Google", "Oracle", "Facebook",
};
var lower = words.Select(x => x.ToLower()).ToArray();
//オブジェクトの例
Console.WriteLine("\n\n-----------------------");
var books = Books.GetBooks();
//タイトルのみのリスト
var titles = books.Select(name => name.Title);
foreach (var title in titles)
{
Console.Write(titles + " ");
}
Console.WriteLine("\n\n-----------------------");
//ページの多い順に並べ替え(または金額の高い順)
var sortedBooks = books.OrderByDescending(book => book.Pages);
foreach (var book in sortedBooks)
{
Console.WriteLine(book.Title + " " + book.Pages);
}
}