Create a set of ? (You can change the question mark to anything you want: int, double, struct, etc.)

Write a C++ program that has three functions:

Function 1: union (set1, set2, result)

Function 2: intersection (set1, set2, result)

subset (set1, set2): boolean The subset function should return true if set1 is a subset of set2, and false otherwise

Note: You cannot use any built-in functions of the C++ set class.