How to make correct output in a file?

Question

C++ / C#

There is a code that cuts out the information I need. (But not correctly)

string[] lines = File.ReadAllLines("C:\\1.xml");
            IEnumerable<string> xmlLines = lines.Where(x => x.Contains("<Types>"));
            HashSet<string> xmlLinesHashSet = new HashSet<string>(xmlLines);
            string[] sorted = xmlLinesHashSet.ToArray();
            File.WriteAllLines ("C:\\2.xml", sorted);

produces the correct result, but not quite. I want it to also remove the "<"type">" tags and save the values ​​in one line.
View source:

<Types>1526 1528765 </Types>
      <Types>1526 152025 </Types>
      <Types>1572 152761 152662 </Types>

And I want the conclusion like this
1526 1528765 1526 152025 1572 152761 152662
Either just everything in a column (much better)

Answer 1

Learn what xml is and how to work with it.

Answer 2

https://metanit.com/sharp/tutorial/16.2.php