Distinguishing extra element from two arrays?

Question

One of my friend was asked this question in an interview -

• You have given two integer arrays each of size 10.
• Both contains 9 equal elements (say 1 t

Answer 1

In LINQ:

var unique1 = (from a in arrayA where !arrayB.Contains(a) select a).First();
var unique2 = (from b in arrayB where !arrayA.Contains(b) select b).First();
return new Pair(unique1, unique2);

...

public sealed class Pair
{
    public T0 Item1 {get;set;}
    public T1 Item2 {get;set;}
    public Pair(T0 item1, T1 item2)
    {
        Item1 = item1;
        Item2 = item2;
    }
    //plus GetHashCode, equality etc.
}