I am trying to print numbers from 1 to 100 without using loops, using C#. Any clues?
With regular expressions
using System.Text.RegularExpressions;
public class Hello1
{
public static void Main()
{
// Count to 128 in unary
string numbers = "x\n";
numbers += Regex.Replace(numbers, "x+\n", "x$&");
numbers += Regex.Replace(numbers, "x+\n", "xx$&");
numbers += Regex.Replace(numbers, "x+\n", "xxxx$&");
numbers += Regex.Replace(numbers, "x+\n", "xxxxxxxx$&");
numbers += Regex.Replace(numbers, "x+\n", "xxxxxxxxxxxxxxxx$&");
numbers += Regex.Replace(numbers, "x+\n", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx$&");
numbers += Regex.Replace(numbers, "x+\n", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx$&");
// Out of 1..128, select 1..100
numbers = Regex.Match(numbers, "(.*\n){100}").Value;
// Convert from unary to decimal
numbers = Regex.Replace(numbers, "x{10}", "<10>");
numbers = Regex.Replace(numbers, "x{9}", "<9>");
numbers = Regex.Replace(numbers, "x{8}", "<8>");
numbers = Regex.Replace(numbers, "x{7}", "<7>");
numbers = Regex.Replace(numbers, "x{6}", "<6>");
numbers = Regex.Replace(numbers, "x{5}", "<5>");
numbers = Regex.Replace(numbers, "x{4}", "<4>");
numbers = Regex.Replace(numbers, "x{3}", "<3>");
numbers = Regex.Replace(numbers, "x{2}", "<2>");
numbers = Regex.Replace(numbers, "x{1}", "<1>");
numbers = Regex.Replace(numbers, "(<10>){10}", "<100>");
numbers = Regex.Replace(numbers, "(<10>){9}", "<90>");
numbers = Regex.Replace(numbers, "(<10>){8}", "<80>");
numbers = Regex.Replace(numbers, "(<10>){7}", "<70>");
numbers = Regex.Replace(numbers, "(<10>){6}", "<60>");
numbers = Regex.Replace(numbers, "(<10>){5}", "<50>");
numbers = Regex.Replace(numbers, "(<10>){4}", "<40>");
numbers = Regex.Replace(numbers, "(<10>){3}", "<30>");
numbers = Regex.Replace(numbers, "(<10>){2}", "<20>");
numbers = Regex.Replace(numbers, "(<[0-9]{3}>)$", "$1<00>");
numbers = Regex.Replace(numbers, "(<[0-9]{2}>)$", "$1<0>");
numbers = Regex.Replace(numbers, "<([0-9]0)>\n", "$1\n");
numbers = Regex.Replace(numbers, "<([0-9])0*>", "$1");
System.Console.WriteLine(numbers);
}
}
The output:
# => 1
# => 2
# ...
# => 99
# => 100