tasks a-s

Task/Catalan-numbers/C/catalan-numbers-1.c

@@ -0,0 +1,46 @@
+#include <stdio.h>
+
+typedef unsigned long long ull;
+
+ull binomial(ull m, ull n)
+{
+	ull r = 1, d = m - n;
+	if (d > n) { n = d; d = m - n; }
+
+	while (m > n) {
+		r *= m--;
+		while (d > 1 && ! (r%d) ) r /= d--;
+	}
+
+	return r;
+}
+
+ull catalan1(int n) {
+	return binomial(2 * n, n) / (1 + n);
+}
+
+ull catalan2(int n) {
+	int i;
+	ull r = !n;
+
+	for (i = 0; i < n; i++)
+		r += catalan2(i) * catalan2(n - 1 - i);
+	return r;
+}
+
+ull catalan3(int n)
+{
+	return n ? 2 * (2 * n - 1) * catalan3(n - 1) / (1 + n) : 1;
+}
+
+int main(void)
+{
+	int i;
+	puts("\tdirect\tsumming\tfrac");
+	for (i = 0; i < 16; i++) {
+		printf("%d\t%llu\t%llu\t%llu\n", i,
+			catalan1(i), catalan2(i), catalan3(i));
+	}
+
+	return 0;
+}

Task/Catalan-numbers/C/catalan-numbers-2.c

@@ -0,0 +1,114 @@
+namespace CatalanNumbers
+{
+    /// <summary>
+    /// Class that holds all options.
+    /// </summary>
+    public class CatalanNumberGenerator
+    {
+        private static double Factorial(double n)
+        {
+            if (n == 0)
+                return 1;
+
+            return n * Factorial(n - 1);
+        }
+
+        public double FirstOption(double n)
+        {
+            const double topMultiplier = 2;
+            return Factorial(topMultiplier * n) / (Factorial(n + 1) * Factorial(n));
+        }
+
+        public double SecondOption(double n)
+        {
+            if (n == 0)
+            {
+                return 1;
+            }
+            double sum = 0;
+            double i = 0;
+            for (; i <= (n - 1); i++)
+            {
+                sum += SecondOption(i) * SecondOption((n - 1) - i);
+            }
+            return sum;
+        }
+
+        public double ThirdOption(double n)
+        {
+            if (n == 0)
+            {
+                return 1;
+            }
+            return ((2 * (2 * n - 1)) / (n + 1)) * ThirdOption(n - 1);
+        }
+    }
+}
+
+
+// Program.cs
+using System;
+using System.Configuration;
+
+// Main program
+// Be sure to add the following to the App.config file and add a reference to System.Configuration:
+// <?xml version="1.0" encoding="utf-8" ?>
+// <configuration>
+//  <appSettings>
+//    <clear/>
+//    <add key="MaxCatalanNumber" value="50"/>
+//  </appSettings>
+// </configuration>
+namespace CatalanNumbers
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            CatalanNumberGenerator generator = new CatalanNumberGenerator();
+            int i = 0;
+            DateTime initial;
+            DateTime final;
+            TimeSpan ts;
+
+            try
+            {
+                initial = DateTime.Now;
+                for (; i <= Convert.ToInt32(ConfigurationManager.AppSettings["MaxCatalanNumber"]); i++)
+                {
+                    Console.WriteLine("CatalanNumber({0}):{1}", i, generator.FirstOption(i));
+                }
+                final = DateTime.Now;
+                ts = final - initial;
+                Console.WriteLine("It took {0}.{1} to execute\n", ts.Seconds, ts.Milliseconds);
+
+                i = 0;
+                initial = DateTime.Now;
+                for (; i <= Convert.ToInt32(ConfigurationManager.AppSettings["MaxCatalanNumber"]); i++)
+                {
+                    Console.WriteLine("CatalanNumber({0}):{1}", i, generator.SecondOption(i));
+                }
+                final = DateTime.Now;
+                ts = final - initial;
+                Console.WriteLine("It took {0}.{1} to execute\n", ts.Seconds, ts.Milliseconds);
+
+                i = 0;
+                initial = DateTime.Now;
+                for (; i <= Convert.ToInt32(ConfigurationManager.AppSettings["MaxCatalanNumber"]); i++)
+                {
+                    Console.WriteLine("CatalanNumber({0}):{1}", i, generator.ThirdOption(i));
+                }
+                final = DateTime.Now;
+                ts = final - initial;
+                Console.WriteLine("It took {0}.{1} to execute", ts.Seconds, ts.Milliseconds, ts.TotalMilliseconds);
+                Console.ReadLine();
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine("Stopped at index {0}:", i);
+                Console.WriteLine(ex.Message);
+                Console.ReadLine();
+            }
+        }
+    }
+}