میانگین(Average)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Average
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            string c;
            Console.WriteLine("a&b&c:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            c = Console.ReadLine();
            float a1 = Int32.Parse(a);
            float b1 = Int32.Parse(b);
            float c1 = Int32.Parse(c);
            float d = (a1 + b1 + c1) / 3;
            Console.WriteLine("Result:" + d.ToString());
            Console.ReadLine();
        }
    }
}

فاکتوریل(Factorial)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Factorial
{
    class Program
    {
        static void Main(string[] args)
        {
            string n;
            Console.WriteLine("n!");
            n = Console.ReadLine();
            int n1 = Int32.Parse(n);
            int z = --n1;
            n1++;
            while(z!=0)
            {
                n1 = n1 * z;
                z--;
            }
            Console.WriteLine("Result:" + n1.ToString());
            Console.ReadKey();
        }
    }
}

ماکسیمم(Maximum)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Maximum
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("n:");
            int n = int.Parse(Console.ReadLine());
            double[] a = new double[n];
            for (int v = 0; v < n; v++)
            {
                a[v] = double.Parse(Console.ReadLine());
            }

            double max = a[0];
            for (int i = 1; i < n; i++)
            {
                if (a[i] > max)
                    max = a[i];
            }
            //double t = z(a[],n);
            Console.WriteLine(Program.maximum(a, n));
            Console.ReadLine();
        }


        static double maximum(double[] a, int n)
        {
            double max = a[0];
            for (int i = 1; i < n; i++)
            {
                if (a[i] > max)
                    max = a[i];
            }
            return max;
        }
    }
}

فیبوناچی(Fibonacci)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Fibonacci
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("n:");
            int n = int.Parse(Console.ReadLine());
            int[] z = new int[n];

            c(z, n);
            for (int q = 0; q < n; q++)
            {
                Console.WriteLine(z[q]);
            }
            Console.ReadLine();
        }
        static void c(int[] a, int n)
        {
            a[0] = 1;
            a[1] = 2;
            for (int i = 2; i < n; i++)
            {
                a[i] = a[i - 1] + a[i - 2];
            }
        }
    }
}

ک.م.م(Least Common Multiple)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Least Common Multiple
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            int a1 = Int32.Parse(a);
            int b1 = Int32.Parse(b);
            int x;
            if (a1 > b1)
            {
                x = a1;
            }
            else
            {
                x = b1;
            }

            int c1, c2;
            c1 = x % a1;
            c2 = x % b1;
            while (c1 != 0 || c2 != 0)
            {
                x++;
                c1 = x % a1;
                c2 = x % b1;

            }
            Console.WriteLine("Result : " + x);
            Console.ReadLine();
        }
    }
}

توان(Power)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Power
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.BackgroundColor = ConsoleColor.Cyan;
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            int a1 = Int32.Parse(a);
            int b1 = Int32.Parse(b);
            int c = 1;
            while (b1 != 0) 
            {
                c = c * a1;
                b1 = b1 - 1;}
            Console.WriteLine("result:" + c.ToString());
            Console.ReadKey();
        }
    }
}

تقسیم(Division)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Division
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            float a1 = float.Parse(a);
            float b1 = float.Parse(b);
            float c = a1 / b1;
            Console.WriteLine("result:" + c.ToString());
            Console.ReadKey();
        }
    }
}

ضرب(Multiplication)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Multiplication
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            int a1 = Int32.Parse(a);
            int b1 = Int32.Parse(b);
            int c = a1 * b1;
            Console.WriteLine("result:" + c.ToString());
            Console.ReadKey();
        }
    }
}

تفریق(Subtraction)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Subtraction
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            int a1 = Int32.Parse(a);
            int b1 = Int32.Parse(b);
            int c = a1 - b1;
            Console.WriteLine("Result:" + c.ToString());
            Console.ReadKey();

        }
    }
}

جمع (Sum)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Sum
{
    class Program
    {
        static void Main(string[] args)
        {
            string a;
            string b;
            Console.WriteLine("a&b:");
            a = Console.ReadLine();
            b = Console.ReadLine();
            int a1 = Int32.Parse(a);
            int b1 = Int32.Parse(b);
            int c = a1 + b1;
            Console.WriteLine("Result:" + c.ToString());
            Console.ReadLine(); 
        }
    }
}