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.

Input: Consider Input: Set1: '{2, 5, 16, 18, 20}', Set2: '{18, 20}'. How many elements are there in the union of Set1 and Set2 ?

Output: 5


Input: Consider Input: Set1: '{9, 3}', Set2: '{8, 4}'. How many elements are there in the union of Set1 and Set2 ?

Output: 4


Input: Consider Input: Set1: '{2, 4, 15, 16, 18, 20}', Set2: '{7}'. How many elements are there in the union of Set1 and Set2 ?


Output: 7