In this task, you are given two sets, and you need to count the number of elements at the union of two given sets. A Set is shown by two curly braces and comma-separated numbers inside, like {1, 2, 3}. Union of two given sets is the smallest set which contains all the elements of both the sets. To find the union of two given sets, A and B is a set that consists of all the elements of A and all the elements of B such that no element is repeated.
--------
Question: Set1: '{1, 4, 9, 13, 14, 16, 17, 18}', Set2: '{3, 19}'. How many elements are there in the union of Set1 and Set2 ?

Answer: 10


Question: Set1: '{8, 9, 10, 11, 16}', Set2: '{7, 15}'. How many elements are there in the union of Set1 and Set2 ?

Answer: 7


Question: Set1: '{19, 12}', Set2: '{11, 3, 4}'. How many elements are there in the union of Set1 and Set2 ?

Answer:
5