matrix multiplication in c#

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

namespace matrix_multiplication
{
    class Program
    {
        static void Main(string[] args)
        {
            int i, j;
            int[,] a = new int[2, 2];
            Console.WriteLine("Enter no for 2*2 matrix");
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                    a[i, j] = int.Parse(Console.ReadLine());
                }
            }
            Console.WriteLine("First matrix is:");
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                  Console.Write(a[i,j]+"\t");
                }
                Console.WriteLine();
            }

          
            int[,] b = new int[2, 2];
            Console.WriteLine("Enter no for 2*2 matrix");
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                    b[i, j] = int.Parse(Console.ReadLine());
                }
            }
            Console.WriteLine("second matrix is:");
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                    Console.Write(b[i, j] + "\t");
                }
                Console.WriteLine();
            }

            Console.WriteLine("Matrix multiplication is:");
            int[,] c = new int[2, 2];
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                    
                    
                    c[i,j]=0;
                     for (int k = 0; k < 2; k++)
                     {
                         c[i, j] +=  a[i, k] * b[k, j];
                     }
                 }
            }
            for (i = 0; i < 2; i++)
            {
                for (j = 0; j < 2; j++)
                {
                    Console.Write(c[i, j]+"\t");
                }
                Console.WriteLine();
            }

            Console.ReadKey();
        }
    }
}

output

Enter no for 2*2 matrix
8
7
6
0
First matrix is:
8       7
6       0
Enter no for 2*2 matrix
4
3
2
1
second matrix is:
4       3
2       1
Matrix multiplication is:
46      31
24      18

printing star in v flag shape in c#

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

namespace star_flag
{
    class Program
    {
        static void Main(string[] args)
        {
            int i, j,n;
            Console.WriteLine("Enter no for printing star in flag shape");
            n = int.Parse(Console.ReadLine());
            for (i = 1; i <= n; i++)
            {
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                for (j = n; j >= i; j--)
                {
                    Console.Write(" ");
                }
                 for (j = n-1; j >= i; j--)
                {
                    Console.Write(" ");
                }
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                    Console.WriteLine();
            }
            Console.ReadKey();
        }
    }
}

output

Enter no for printing star in flag shape
6
*           *
**         **
***       ***
****     ****
*****   *****
****** ******

diamond shape in c#

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

namespace star_dimand
{
    class Program
    {
        static void Main(string[] args)
        {
            int i, j,n;
            Console.WriteLine("Enter no for printing star in diamond shape");
            n = int.Parse(Console.ReadLine());
            for (i = 1; i <= n; i++)
            {
                for (j = n; j >= i; j--)
                {
                    Console.Write(" ");
                }
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                for (j = 1; j <= i; j++)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            
          
            for (i = 1; i <= n; i++)
            {
                for (j = 0; j <=i; j++)
                {
                    Console.Write(" ");
                }
                for (j = n; j >= i; j--)
                {
                    Console.Write("*");
                }
                for (j = n; j >= i; j--)
                {
                    Console.Write("*");
                }
                Console.WriteLine();
            }
            Console.ReadKey();
        }
    }
}
output

Enter no for printing star in diamond shape
6
      **
     ****
    ******
   ********
  **********
 ************
  ************
   **********
    ********
     ******
      ****
       **