C# Online Compiler | .NET Fiddle

<no name> by Anonymous

using System;
using System.Collections.Generic;
using System.Linq;

class MainClass {
  public static void Main (string[] args) {
    var test = new List<List<string>>();
    test.Add(new List<string> {"1","2","3"});
    test.Add(new List<string> {"1","4","5"});
    test.Add(new List<string> {"1","2","3"});
    test.Add(new List<string> {"1","4","5"});
    test.Add(new List<string> {"6","7","8"});

    var query = test.OrderBy(a=>a[0]);
    var max = test.Select(a=>a.Count()).Max();
    Console.WriteLine(max);
    for (int i = 1; i < max; i++)
    {
        var j = i;
        query = query.ThenBy(a=>a[j]);
    };
    var sorted = query.ToList();
    foreach(var catGroup in test)
    {
      Console.WriteLine(string.Join(">", catGroup));
    }

    foreach(var catGroup in sorted)
    {
      Console.WriteLine(string.Join(">", catGroup));
    }
  }
}

​x
 
using System;
using System.Collections.Generic;
using System.Linq;
​
class MainClass {
  public static void Main (string[] args) {
    var test = new List<List<string>>();
    test.Add(new List<string> {"1","2","3"});
    test.Add(new List<string> {"1","4","5"});
    test.Add(new List<string> {"1","2","3"});
    test.Add(new List<string> {"1","4","5"});
    test.Add(new List<string> {"6","7","8"});
​
    var query = test.OrderBy(a=>a[0]);
    var max = test.Select(a=>a.Count()).Max();
    Console.WriteLine(max);
    for (int i = 1; i < max; i++)
    {
        var j = i;
        query = query.ThenBy(a=>a[j]);
    };
    var sorted = query.ToList();
    foreach(var catGroup in test)
    {
      Console.WriteLine(string.Join(">", catGroup));
    }
​
    foreach(var catGroup in sorted)
    {
      Console.WriteLine(string.Join(">", catGroup));
    }
  }
}

Roslyn 2.0 Compiler; Environment version: 4.0.30319.42000

<?xml version="1.0" encoding="utf-16"?>
<data xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" someattributea="" someattributeb="" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" />
<?xml version="1.0" encoding="utf-16"?>
<data xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" someattributea="replacement value for Someattributea" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" />

Testing a list of Data.
<?xml version="1.0" encoding="utf-16"?>
<DataList xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <DataItem someattributea="" someattributeb="" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" xmlns="https://Test Namespace" />
  <DataItem someattributea="" someattributeb="" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" xmlns="https://Test Namespace" />
</DataList>
<?xml version="1.0" encoding="utf-16"?>
<DataList xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <DataItem someattributea="" someattributeb="" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" xmlns="https://Test Namespace" />
  <DataItem someattributea="" someattributeb="" someattributec="" ExtraAttr="" p1:someattributec="namespace attr" xmlns:p1="http://SomeTestNamespace.com" xmlns="https://Test Namespace" />
</DataList>

Last Run:	6:50:01 pm
Compile:	1.125s
Execute:	0.29s
Memory:	2.40Mb
CPU:	0.547s

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