A number n is perfect if it is equal to the sum of all its divisors (1 included, n excluded) Example: divisors of 6 are 1, 2, 3 and 6; 1+2+3 66 is a perfect number. Divisors of 8 are 1, 2, 4 and 8; 1+2+4 7->8 is not perfect. Write a C++ program that displays the list of perfect numbers up to n. Where n must be entered by the user; ensure that n is a positive number less than 1000