Check whether an array is a subset of another

Question

Any idea on how to check whether that list is a subset of another?

Specifically, I have

List t1 = new List { 1, 3, 5 };
L         


        

Answer 1

Use HashSet instead of List if working with sets. Then you can simply use IsSubsetOf()

HashSet t1 = new HashSet{1,3,5};
HashSet t2 = new HashSet{1,5};

bool isSubset = t2.IsSubsetOf(t1);

Sorry that it doesn't use LINQ. :-(

If you need to use lists, then @Jared's solution works with the caveat that you will need to remove any repeated elements that exist.