### Problem Statement

A set of numbers is a collection of numbers with no repeated elements. We can define the following set operations:

The UNION of two sets A and B is a set containing all the elements that are either in A or in B.

The INTERSECTION of two sets A and B is a set containing all the elements that are in both A and B.

The SYMMETRIC DIFFERENCE of two sets A and B is a set containing all the elements that are either in A or in B, but not containing elements that are in both A and B.

Given two int[]s representing sets A and B, and an operation applied on them, return a int[] representing the resulting set sorted in ascending order. If the result is an empty set then return an empty int[]. operation will be one of the following: "UNION", "INTERSECTION", "SYMMETRIC DIFFERENCE".

### Definition

 Class: Sets Method: operate Parameters: int[], int[], String Returns: int[] Method signature: int[] operate(int[] A, int[] B, String operation) (be sure your method is public)

### Constraints

-A will have between 0 and 50 elements inclusive.
-B will have between 0 and 50 elements inclusive.
-each element in A will be between -1000000 and 1000000 inclusive.
-each element in B will be between -1000000 and 1000000 inclusive.
-A will not have any repeated elements.
-B will not have any repeated elements.
-operation will be one of the following: "UNION", "INTERSECTION", "SYMMETRIC DIFFERENCE".

### Examples

0)

 `{1,2,3,4}` `{3,4,5,6}` `"INTERSECTION"`
`Returns: { 3,  4 }`
 The only elements that are both in A and in B are 3 and 4.
1)

 `{1,2,3,4}` `{3,4,5,6}` `"UNION"`
`Returns: { 1,  2,  3,  4,  5,  6 }`
 Here we return all the elements that are either in A or in B.
2)

 `{432,756,123}` `{534,76,1209}` `"INTERSECTION"`
`Returns: { }`
 There are no common elements, so we must return an empty set.
3)

 `{6,5,7,4}` `{7,6,4,10}` `"SYMMETRIC DIFFERENCE"`
`Returns: { 5,  10 }`
 Elements 4, 6, 7 are in both sets, thus they cannot be in our answer. However we can include elements 5 and 10.
4)

 `{342,654,897,312,76,23,78}` `{21,43,87,98,23,756,897,234,645,876,123}` `"SYMMETRIC DIFFERENCE"`
`Returns: { 21,  43,  76,  78,  87,  98,  123,  234,  312,  342,  645,  654,  756,  876 }`

#### Problem url:

http://www.topcoder.com/stat?c=problem_statement&pm=1685

#### Problem stats url:

http://www.topcoder.com/tc?module=ProblemDetail&rd=4600&pm=1685