public static void Main()
int sumUnits = 0, sumTens = 0, sumHundreds = 0;
Console.WriteLine("the {0} random number is : {1}",i,num);
sumTens += num % 100 / 10;
sumHundreds += num / 100;
Console.WriteLine("the sum of units digits is : "+sumUnits);
Console.WriteLine("the sum of tens digits is : "+sumTens);
Console.WriteLine("the sum of Hundreds digits is : {0} ",sumHundreds);