gushwell

 class Program {
     static void Main(string[] args) {
         Console.WriteLine(Gcd(0, 8));
         Console.WriteLine(Gcd(12, 8));
         Console.WriteLine(Gcd(3400, 6596));
         Console.WriteLine(Gcd(12707, 12319));
     }
     // ユークリッドの互除法 
     public static int Gcd(int a, int b) {
         if (a < b)

gushwell

  public static long Fibo(int n) {
      if (n == 0)
          return 0;
      if (n == 1)
          return 1;
      return Fibo(n - 1) + Fibo(n - 2);
  }

gushwell

using System;
using System.Linq;

namespace Gushwell.Etude {
    class Program {
        static void Main(string[] args) {
            // 1 - 100 までのメビウス関数を求める
            int upper = 100;
            Mebius mebius = new Mebius(upper);
            for (int i = 1; i <= upper; i++) {

gushwell

 // 下限、上限が指定できるbool型配列
 class BoundedBoolArray {
     private BitArray _array;
     private int _lower;

     public BoundedBoolArray(int lower, int upper) {
         _array = new BitArray(upper - lower + 1);
         _lower = lower;
     }

gushwell

 static IEnumerable<int> Primes(int maxnum) {
     // var sieve = new BitArray(maxnum + 1, true);
     bool[] sieve = Enumerable.Repeat(true, maxnum + 1).ToArray();
     int squareroot = (int)Math.Sqrt(maxnum);
     for (int i = 2; i <= squareroot; i++) {
         if (sieve[i] == false)
             continue;
         for (int n = i * 2; n <= maxnum; n += i)
             sieve[n] = false;
     }

gushwell

public static long Factorial(int n) {
    if (n == 0)
        return 1L;
    return n * Factorial(n - 1);
}

gushwell

using System;
using System.Windows;
using System.Windows.Media.Imaging;
namespace DataTemplateSample {
    public partial class MainWindow : Window {
        public MainWindow() {
            InitializeComponent();
        }
        private void Window_Loaded(object sender, RoutedEventArgs e) {
            MyImage mi = new MyImage();