using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
 
namespace dotnetRegex
{
    class Program
    {
        static void Main(string[] args)
        {
            var text = $"{Environment.NewLine}a{Environment.NewLine}b";
 
            var patN = @"^.*$";
            var reN = new Regex(patN);
            var msN = reN.Matches(text);
            Console.WriteLine($"Begin and end specified: {msN.Count}");
            Console.WriteLine();
 
            var patB = @"^.*";
            var reB = new Regex(patB);
            var msB = reB.Matches(text);
            foreach (var mB in msB)
                Console.WriteLine($"Begin specified only   : {string.Join(" ", mB.ToString().Select(c => (int)c))}");
            Console.WriteLine();
 
            var patE = @".*$";
            var reE = new Regex(patE);
            var msE = reE.Matches(text);
            foreach (var mE in msE)
                Console.WriteLine($"End specified only     : {string.Join(" ", mE.ToString().Select(c => (int)c))}");
        }
    }
}
 

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