Write a program in C# Sharp to find maximum occurring character in a string

using System;  
public class Exercise10  
{  
    public static void Main() 
{
    string str;
    int[] ch_fre = new int[255];
    int i = 0, max,l;
    int ascii;	
      Console.Write("\n\nFind maximum occurring character in a string :\n");
      Console.Write("--------------------------------------------------\n"); 	
      Console.Write("Input the string : ");
      str = Console.ReadLine();	
      l=str.Length;
    for(i=0; i<255; i++)  //Set frequency of all characters to 0
    {
        ch_fre[i] = 0;
    }
    /* Read for frequency of each characters */
    i=0;
    while(i<l)
    {
        ascii = (int)str[i];
        ch_fre[ascii] += 1;
        i++;
    }
// Console.Write("{0}  ",(char)65);
    max = 0;
    for(i=0; i<255; i++)
    {
      if(i!=32)
        {
        if(ch_fre[i] > ch_fre[max])
            max = i;
        }
    }
   Console.Write("The Highest frequency of character '{0}' is appearing for number of times : {1} \n\n", (char)max, ch_fre[max]);
	}
}