using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running; 

BenchmarkSwitcher.FromAssembly(typeof(Tests).Assembly).Run(args); 

[HideColumns("Job", "Error", "StdDev", "Median", "RatioSD")]
public class Tests
{
    private static readonly string s_input = new HttpClient().GetStringAsync("https://gutenberg.org/cache/epub/2600/pg2600.txt").Result;
    private static readonly string[] s_daysOfWeek = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"];

    [Benchmark]
    public bool Contains_Iterate()
    {
         ReadOnlySpan<char> input = s_input;
         for (int i = 0; i < input.Length; i++)
         {
             foreach (string dow in s_daysOfWeek)
             {
                 if (input.Slice(i).StartsWith(dow, StringComparison.OrdinalIgnoreCase))
                 {
                     return true;
                 }
             }
         }
         return false;
     }
}