linq-vs-loop-vs-regex, C#

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public static class Program
    {
        static bool hasTwoPeriodsLinq(string text)
        {
            return text.Count(x => x == '.') == 2;
        }
        
        static bool hasTwoPeriodsLoop(string text)
        {
            int count = 0;
            
            for (int i = 0; i < text.Length; i++)
            {
                if (text[i] == '.')
                {
                    // This early break makes the loop faster than regex
                    if (count == 2)
                    {
                        return false;
                    }
                    
                    count++;
                }
            }
            
            return count == 2;
        }
        
        static Regex twoPeriodsRegex = new Regex(@"^.*\..*\..*$", RegexOptions.Compiled);
        
        static bool hasTwoPeriodsRegex(string text)
        {
            return twoPeriodsRegex.IsMatch(text);
        }
        
        public static void Main(string[] args)
        {
            var text = @"The young Princess Bolk6nskaya had 
brought some work in a gold-embroidered vel- 
vet bag. Her pretty little upper lip, on which 
a delicate dark down was just perceptible, was 
too short for her teeth, but it lifted all the more 
sweetly, and was especially charming when she 
occasionally drew it down to meet the lower 
lip. As is always the case with a thoroughly at- 
tractive woman, her defectthe shortness of 
her upperlip and her half-open mouth seemed 
to be her own special and peculiar form of 
beauty. Everyone brightened at the sight of 
this pretty young woman, so soon to become 
a mother, so full of life and health, and carry- 
ing her burden so lightly. Old men and dull 
dispirited young ones who looked at her, after 
being in her company and talking to her a 
litttle while, felt as if they too were becoming, 
like her, full of life and health. All who talked 
to her, and at each word saw her bright smile 
and the constant gleam of her white teeth, 
thought that they were in a specially amiable 
mood that day. ";
            
            const int iterations = 100000;
            
            // Warm up... 
            for (int i = 0; i < iterations; i++)
            {
                hasTwoPeriodsLinq(text);
                hasTwoPeriodsLoop(text);
                hasTwoPeriodsRegex(text);
            }
            
            var watch = System.Diagnostics.Stopwatch.StartNew();
            
            // hasTwoPeriodsLinq
            watch.Restart();
            
            for (int i = 0; i < iterations; i++)
            {
                hasTwoPeriodsLinq(text);
            }
            
            watch.Stop();
            
            Console.WriteLine("hasTwoPeriodsLinq " + watch.ElapsedMilliseconds);
            
            // hasTwoPeriodsLoop
            watch.Restart();
            
            for (int i = 0; i < iterations; i++)
            {
                hasTwoPeriodsLoop(text);
            }
            
            watch.Stop();
            
            Console.WriteLine("hasTwoPeriodsLoop " + watch.ElapsedMilliseconds);
            
            // hasTwoPeriodsRegex
            watch.Restart();
            
            for (int i = 0; i < iterations; i++)
            {
                hasTwoPeriodsRegex(text);
            }
            
            watch.Stop();
            
            Console.WriteLine("hasTwoPeriodsRegex " + watch.ElapsedMilliseconds);
        }
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0,14 sec, absolute running time: 3,02 sec, cpu time: 3,03 sec, average memory usage: 26 Mb, average nr of threads: 5