Write a program in C# Sharp to find sum of rows an columns of a Matrix

using System;  
public class Exercise25
{  
    public static void Main()
{
     int i,j,n;
	    int[,] arr1 = new int[10,10];
		int[] rsum = new int[10];
		int[] csum = new int[10];	 
       Console.Write("\n\nFind sum of row an column of a Matrix:\n ");
       Console.Write("-------------------------------------------\n");	 
     Console.Write("Input the size of the square matrix : ");
	 n = Convert.ToInt32(Console.ReadLine());	 
	 Console.Write("Input elements in the matrix :\n");
       for(i=0;i<n;i++)
        {
            for(j=0;j<n;j++)
            {
	           Console.Write("element - [{0}],[{1}] : ",i,j);
			   arr1[i,j]=Convert.ToInt32(Console.ReadLine());
            }
        }  
	 Console.Write("The matrix is :\n");
	 for(i=0;i<n;i++)
	 {
	   for(j=0;j<n ;j++)
	     Console.Write("{0}  ",arr1[i,j]);
	    Console.Write("\n");
	 }
     /* Sum of rows */
     for(i=0;i<n;i++)
     {
	  rsum[i]=0;
	  for(j=0;j<n;j++)
	  rsum[i]=rsum[i]+arr1[i,j];
     }
      /* Sum of Column */
      for(i=0;i<n;i++)
      {
	  csum[i]=0;
	  for(j=0;j<n;j++)
		csum[i]=csum[i]+arr1[j,i];
      }
      Console.Write("The sum or rows and columns of the matrix is :\n");
      for(i=0;i<n;i++)
      {
	   for(j=0;j<n;j++)
	   Console.Write("{0}    ",arr1[i,j]);
	   Console.Write("{0}    ",rsum[i]);
	   Console.Write("\n");
       }
       Console.Write("\n");
	    for(j=0;j<n;j++)
             {
	        Console.Write("{0}   ",csum[j]);
             }
            Console.Write("\n\n"); 
		}	
  }