intersection
Find the intersection of the sets of elements in two arrays.
y=intersection(a, b)
Inputs
a Any array.
b Any array, but must be a of the same type as the first input.
Outputs
y A one-dimensional array of unique elements that are elements of both of the inputs.


Example
>>intersection([2 3 4 2],[ 1 2 78 8 23 2])
         2
>>intersection({"usa","usa","canada"},{"brazil","canada"})
[canada]